I like my 3D set-up to be fast,forgiving,and comfortable to shoot.Many people think speed is the name of the game!!!! It's not.A 3D set up IMHO should be easy to shoot,being over-bowed is what I see alot of on the 3D circuit.
The bow needs to have the proper balance,poundage,DRAWLENGTH,and set up with the right arrows.
I do not seek the speed,I shoot my best with a bow that shoots right around 278-283 fps.Anything faster seems to be less controlable for me.The IBO has a 5gr per pound minimum for arrow weight,I try to stay as close to that as possible but stay also with whatever arrows shoot and groups the best,not whichever one is fastest.
Bow set-ups are a personal thing,what works for some will not for others.
My set up consists of:
Mathews Q2XL 28" at 65#
Sure-loc lite sight w/ Bullseye 4X AP Scope
Trophy-Taker fall-away rest
30" Easton Black Max Stabilizer
Cavalier V-Bar w/two 8" Super Stix stabs
Easton ACC 3-39's w/70gr point and 2.3" Duravanes OR
Linejammer 350's w/90gr point and 2.3" Duravanes
Stanislawski Mirage or Carter BK Target release (whichever one is working best on the given day).

Best advice I can give is to try different things,and talk to people who use the things you are interested in.
Archery is a very individual thing.