I have an old Diamond Express 56i. Not the greatest. I would recommend anything US Robotics, but they do cost an arm or a leg, or your first newborn son.

In the early 56K days, I tested a LOT of modems, and even helped a few others to discover the broken Data Pump in the Rockwell chipped modems that prevented upgrades to the new V90 (Hayes was the biggest offender and LIAR!!!!). And though I was an avid Supra supporter for many many years (since their old 1200 baud), I have to say this. IF you still want to stay on a modem, the USR/3COM modems are the strongest and the best to get you as good a speed as possible limited by your phone lines. BUT!!! Why stay on an antiquated modem line? Try to go with DSL!!! My phone lines are junk, so I was never able to get more than 38K on a modem, and until recently could not get DSL. But when I went to www.dslreports.com - I found a DSL provider, Speakeasy, that could at least give me a 144K iDSL line! Now I may not get as good as others with real DSL, but 144K is waaaaaay better than 38K.

Although when 56k first came out and then the old 28.8 modems USR\3COM ruled. But their modems suck now with a capitol S. You ever try searching for 3COM drivers. I would swear by thier Lan cards but as for thier modems they suck. Go with Diamond Always been a damn good modem and easy to find drivers and support.
 
 
Just my 2 Cents