with your motherboard you could only upgrade to the phenom II i believe, you want to check the manufacturers website for the cpu compatability list.
Ah. Thank you for mentioning that. It seems they are compatible with my motherboard, i'd just have to update my BIOS for the FXs to work according to ASUS' page for it. The Phenom II definitely looks more favorable being less of a hassle to setup in that regard.
However, I still do want a comparison of performance between these 3 for the price. If the performance difference is good enough in the FXs over the Phenom, I feel it'd be worth the extra work (plus the $4-5 less as well)