Here's how it goes: all 3 are stable and fast and good, yadda yadda.
The EPoX is cheapest because though it has firewire, USB2, AGP8X, ATA133, nForce sound, 10/100, etc, it lacks a second 10/100, SATA, and digital nForce sound output.
The Asus has that talking voice diagnostic thingy and SATA, a second 10/100, and digital sound. The Abit has digital sound, a second 10/100, SATA, and even an SATA drive adapter. You take your pick.
Basically, the EPoX is a fine board for those who do not need SATA, digital sound, or two network controllers. It's missing those features, but at 1/3 less cost, why not?
<--Uses an 8RDA+