Recommended Upgrades - Magna Clutch kit, Hybrid or Powerlite Shells, Long antijam spring
Starting by saying that I've used a B2 for almost a year now, I had a B1 for about 4 years but the board finally broke. Replaced it with a B2 board and am never going back. The only thing you should do is add the Magna Clutch Kit
Pros
Fast - 6 speed settings nother else is needed for speed, the B2 on speed 4 feeds about 20 BPS nothing more is needed.
Reliable - if it doesn't work 100% of the time bump the sound up 1. If you ever have a problem replace the batteries.
Adjustability - with 6 speed settings, 6 sound settings and 2 stack settings can't ask for anything more
Cons
Shells - the stock shells are pretty solid but I like the powerlyte shells MUCH more.
Conclusion:
Fast, reliable loader that you'll love.
8 out of 10 it'd get a solid 9.5 if it had hybrid style shells and a clutch kit stock