BTW, if you end up buying a BOSS GT-series, theres a little trick to get it to sound real good. It's called "4 cable method"...
Basically, you run your guitar through the pedal, then, there's somewhere a function for external distortion or effects or whatever (in my GT-3 it's in OD/DS.) So you run that output to your amp's input. The amp's effect loop out goes into the external OD in and the pedal's output finally goes to the power-amp's IN (Read: effects loop in)
Now, with the "effect chain" function, you can put any effect before or after your preamp... Useful if you want, say: Compressor, EQ, (preamp), reverb, delay, (poweramp)
Hope it helps