BEFB = BSLB + DMA4
BEGB = BSNB + DMA4
BEFB is better if you're going to use your drive externally and as a scanner. It doesn't have the speed dips or other reading problems that later firmwares had, just like BSLB.
And Firewire is always preferable to USB2, even if you aren't noticing specific problems. Scans are more accurate, PIE on burns is lower, etc.
BEFB + Firewire = Best External Configuration