I'm looking for a simple/cheap interface (preferably USB) to plug a guitar or a bass in my Mac. I know about full-featured interfaces like M-Audio Fast Track but they're a bit overkill for me. I already have a good USB mic to record voice/acoustic guitar and just want a simple way to plug my guitar and record some riffs using software amp simulation.
I found this one at Amazon for $20, but I don't really know if it's good or not. Any recommendations?