you forgot about qVault! here's what i think of each:
-qVault: awesome for every single section (I didn't try the RC tho)
-bootcamp: awesome for every single section (a little harder) except for QR (BC is much harder)
-achiever: haven't tried it, but I head it is much harder than the real thing, why kill your self-esteem?
-topscore: awesome representation! loved it
-cracker: incomplete, repetitive questions, much easier than the real thing
-Crack DAT: i tried the PAT, but bootcamp PAT is MUCH better, I header its RC and QR are pretty good, science too easy