I personally have only used the Creatine E2 (LOVED IT!!!!), but I think this is going to become a matter of what you are looking for:
from what I understand...
Creatine E2 - just Creatine Ethyl Ester
Creatine E2 Matrix - Creatine Ethyl Ester / Nitric Oxide Hybrid
CVM - workout support supplement with creatine, nitric oxide precursors, creatine production supporters, etc.
Since you want the most bang...probably go with the CVM, but since you are taking Xtend which has nitric oxide precursors in it, you could just add the Creatine E2 and have your BCAAs, NO precursors and CE2 all in one shot.
Either way, you can't go wrong with SNS products; they rock!
...just my $0.02 though.