As a long time MSF instructor I highly recommend the class for any new riders. There are many benefits to the class to include safe riding techniques, getting your endorsement in a weekends time and reduced motorcycle insurance. You learn on state supplied motorcycles (150 and 250cc Yamahas, Hondas, Suzukis etc.)so you don't have to own one to begin with. Another benefit to keep in mind and to always ask is that many bike shops, accessories shops and parts suppliers will give a discount to holders of the MSF course.
HD Riders Edge and the MSF course are virtually identical in program content. The big difference is that HD typically gives a tour of one of their dealerships (and lets you buy stuff$$$), The Riders Edge course can cost almost double what the MSF course will cost, but you are riding a Buell rather than a Honda or Yamaha.
Either way you go, training and practice is vital. MSF also offers the ERC (Experienced Riders Course) which is usually a 5 -6 hour one day program. You use your own motorcycle and perform a variety of different exercises (form multiple curves, accident avoidance, slow speed manuevers, etc.) and it is a great way of beginning a riding season. Here in MN it is only $55 so well worth the price of admission.