The Boss GT-8 kills anything digitech or line 6 have to offer as far as sound/effect/tones go...if you need bells n' whistles then the GNX4 might be for you,but its overpriced and the pod xt live is a far better value.

In order...

1.Boss GT-8
2.PODXT Live
3.Digitech GNX4

but it really comes down to why you need it/what purpose it will serve.For me,tone comes first,so I can live without a drum machine and 8-track.It might be different for you.

here is the boss pedal...


The pedals wars begun they have...