I'm using the Line6 mobile and it is just absolutly unbelievable!!! also you can play along with you favorite tunes and you can download complete original songs with the guitarist ripped out of the mix from http://www.guitarbackingtrack.com/
try AC\DC whole lotta rosie, live version and you will swear you are Angus playing live in Dodington!!
So I have traied a lot of guitars and I have a few absolute favourites so I have ferreted out some of my favourites. This includes some of the gear I already have. So I have reseerched a ton of stuff and put it all together on this website. Check it out if you have time: www.musicandguitars.com