The non-adjustable ones have a slight timing advance, which is all you really need: I've played with the adjustable ones and moving it too much in any direction (advance or retard the timing) and the buggy starts running very rough - if it stay running at all.
The non-adjustable ones are plug-and-play. No additional tuning required.
The camshafts that will give you more mid-range are the A10-A11 range. The A8 & A9 will lean towards more top end, and anything A12 and above is a significant low end boost.
As for shocks, there really aren't any that are made specifically for the buggies. We generally are cannibalizing them from other vehicles (like yamaha blaster front shocks). On top of that, the real trick is finding some that fit your specific model with a decent price. I'm really not much help on that front.
