I will throw my input on why I went with the PDM verse WP. First is that since BD first mentioned that they were going to have retrofit, I have been saying that I would give it a try. When they came out with one, I decided to follow up on doing so.
I thought long and hard between it and the WP and since I was still running with a EHC, decided to give the PDM a try. Main reason was that it came from BDPP and was their designed. It allows one to basically disconnect the JST from the old, remove the harness/s and EHC without cutting them all up, and then install a complete new wire harness hooking up to the original JST connectors, as well as a PDM module that seem to be pretty well built.
The PDM module has simple relays and fuses in the box that will help protect circuits (or at least I hope so).
In addition it came from BD and even though I do most of my work myself, it is nice that there is some commonality to the kits that should allow for easier troubleshooting and trace of circuits.
Also, since I took my time and took out the old without cutting anything up, worse case I can reinstall if needed until a better fix comes up (barring that the PDM does not hold up).
The WP appears to be a good kit and WP in general has a very good reputation. I know some of the tech at my dealer have installed a few and seem to be happy with it.
Other than wanting to give BD a try and see if they nailed it with their PDM (I think they did but time will tell), the main thing keeping me shy of the WP was that it was not direct fit.
WP required the harness connection to be cut off and the wiring to install into the WP DIN connector with some minor changes in the routing. Nothing wrong with that, but since ones does cut off the harness, all those wires (and there is many) have to have ends crimped (may also consider soldering) to each wire, properly landed which can lead to more concerns of bad pin connectors (dry sockets if soldering), tight connections due to the original wire is shorter leaving less room to work with and various other concerns that can arise on anything involving electrical circuits.
Last but not least, the PDM comes with a wiring harness and assuming that one does not F up that harness and it was good to begin with, less chance of a short or grounded wire. With the WP, even after one does a proper install, there is still a chance that whatever caused the problem in the first place could be in the wiring harness and one may have spent a good amount of time to only find out the problem that caused the EHC to fail or acted up was actually in the wiring harness which may still be there with the WP.
The WP as I said seems to be a very good product and the company does have a good reputation. It just involved more install efforts on the installer part and this increases the chance for additional headaches if the connectors come loose, crossed wiring, bad solder, etc. No doubt that this can occur on any electrical circuit and in fact even on my PDM that I got, the fabricator did land three of the wires in the wrong location (easy fix, little time to find), still I see this has more likely occurring with a WP than PDM
Now the PDM you do lose some items and to the best of my knowledge one only looses the self cancel feature of the turn signals and the emergency flasher feature. It is somewhat frustrating that BDPP did not include those in the PDM, but I will assume that there was a reason. Not a big deal to me, for with the exception of the BD, none of my other MC had these feature to begin with and that includes my 2009 Buell.
The WP you keep these.
The PDM (at least for the ones that have to have the battery tray replaced) are more expensive than the WP, but I think they are pretty close by the time you throw in all the aspects of the WP such as the new ignition switch. The PDM for the 300 tires goes for about $621 verse $520 for the WP kit. The PDM for the 250 kit that need a battery tray go for $703. The WP is still $520. On the WP the $520 is just of the WP and does not have a new wiring harness and if going with recommendation there is another $60 to add on if you go with the recommended High Voltage switch ($40 roundup) plus Duetch (sp) 3 pin connector at $20. So if going with the recommendation of WP, it will run you around $580 (not including any Group buys that my pop up from time to time or the tools that may need to be purchased like good crimpers).
PDM from my experience is about 4 hours install (may be more or less depending on how you land wires and how much issues you have getting backbone harness installed). I cannot say for the WP, but from information I have read of those that have installed a few as well as talking to my dealer which has done well over 20 now, average time with knowledge is 6-7 hours, newbees can be quite a bit more.
It is each and everyone own call. The PDM appears to be well made, has numerous fuses for the circuits as well as relays, comes with a complete backbone and lower harness, fairly easy to install and you can save the original if you need to go back. Still to be proven for time and stress.
WP has been used by many and many good reports, may take more time, requires extensive connecting from WP to original wiring harness, does not replace the backbone or power harness, has longer real life testing out there and for most seem to be good. The module itself is well protected and solid construction, but does not have fuse/s and relays to help isolate a problem with a possible simple fix of change a fuse or relay like the PDM does. It is lower cost in general but maybe higher in labor (depending on who does it).
Big Dog Performance Parts is the source for the PDM (or your local BD dealer working with BDPP) and it appears that they make the different ones in small batches so availability may take some time. WP may be easier to get depending on the model needed but also may be out of stock waiting for new batches.
Both are options to any EHC problems and allows for support down the road to keep us all up and running.
Last, my EHC was still good and I still have it in case the PDM does not hold up and have to back-load. I only changed it out to give me a little better feeling and want to feel better for whenever I get some time to real ride and put some much needed miles on the Mastiff. Suggest that no matter which route one choose, that you do so knowing the pros-cons for both and if you are now having any issues with your electrical, and not ready to make a swap unless absolutely needed, that you read the many good threads and post on here, maybe hook up with some of your fellow members that have wrenched themselves, and do proper troubleshooting and make sure it is the EHC, There has been many many EHC that were replaced that I am sure were not the root cause, both by members and some stealers.
It always good to have a good multi-meter and if not familiar with electrical circuits, grab a book, a friend that is or both and learn. As Gas man would say, why pay other to F up your bike.
If one is interested in the PDM, you can go on the BDPP web site, if not mistaken, and download the schematic and the installation instruction to give you an idea of what is involved. I would imagine that Wire Plus may also have the same. In addition there is some good thread on here concerning the WP install and tips and a few on the PDM.
Oh MY Disclaimer, I have nothing to do with BDPP, WP or any other companies other than who I work for and my own consulting (which is not MC). I am not a seller, do not sell anything (other consulting for Project and Engineer Management), do not intend to sell anything MC related and pay the same as all the other members on here. I get no special discounts or anything from anyone either. My only interest is the member on this forum that enjoy BD has much as I do and just pass on what I have learned regardless if it is of any use to all, a few or none.
Safe riding to all