I have an 02 Boxer (no compression release) that I always had trouble starting cuz of the week battery that came with it and because I replaced it with the same brand battery first time around. I kept it on a trickle charge and it was still a pain in the ass.
A mechanic I knew told me to put the HD battery in it, so I took the old one to the HD dealer and told him to give me one similar. It cost $90 bucks vs $120. The others lasted 2 years and this one is going on 4. And guess what, I never use the trickle charger anymore. Even when I have deployed for months, I came back threw the charger on it and it would quickly go to Full.
I know a lot of others are using bigger stronger batteries, but I have been completely satisfied with the HD and the price was better than any of the others at the time.