I always put just one drive in my (main) PC, and it's bound to be a Lite-On (short exceptions notwithstanding), but that's just me. They're true all-in-one drives (reading, ripping, burning, scanning,...) and easy to replace when a new one takes your fancy (you won't even see the difference

). Anything else I alternate in external enclosures.
The 1655 and 760A are icons of their day, so I would treat them accordingly. The 1620 would be good for a second scanning opinion.