DFI's advantages are:
1. You pay for parts rather than bling + name
2. You're not adding to the Fatal1ty royality fund
3. Less bling, more performance
4. Performance
Ok on a serious note (although the above isnt far off), the Fatality boards are marketed for bling with only a bit of performance behind it. The DFI LP boards on the otherhands actually have tried and true performance but more importantly, they have flexibility and options! Just going through all the BIOS options can be dizzying
I used a Fatality board (925XE but still, same principle) and while it was a good board and all, cheaper and better boards (at the time, P5AD2-E DLX) were available -- and for less... granted that's on the Intel side of things, but the story is the same.
Dont get me wrong, the Fatality board is nice ... it's just you're paying mostly for the bling and percieved power.