Can you tell the difference between them?, I'm not an expert but hearing a real big fat amp against a computer generated tone... c'mon we are not deaf, and sure we are not idiots.
Bottom line I have to say my pod xt gives me a lot of fun, gives me options, lots of efects (that if purchased one by one could coast me a fortune), wha pedal, pitch shifter (i wish I had a digitech whammy pedal...) but in the end I feel like when I have my double rect (or maybe a Krankstein...mmm...sweet) I feel that I'll understad better how to get good tone out of it. Think of the pod xt as a crash course over amps you can buy today.
Power corrupts. Absolute power is kinda neat.