Premium audio interface with advanced guitar tone shaping
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If you want/need plugins IK Multimedia AXE I/O includes Amplitube Deluxe. It is a bit more $$ total but not a bad deal. They also have a smaller unit (AXE IO Solo) for $100 less (and less software). The SOLO cost is right there with the M4, Zoom, etc Or the fuill size one comes up on Reverb.com or ebay for around $250 as well used (no software likely)
I have the full size one and software and have to say its awesome. GREAT quality, performance, low latency, A5 is pretty darn good software.
I have a RME 9632 in my computer as well and never use it anymore - the AXE is that good.
I tried the MOTU M4 and it was fine (low latency etc) too. But it felt cheap compared to the IK AXE.
There's also the ZOOM UAC -2 that is supposed to have really good latency.
And I've used Behringer as well. Not bad actually for performance.
I think the main thing you want especially with guitar is low latency stability. All of the above (except maybe "B") can go <5ms on my (old i5) with no issues. They've gotten much better.