I don't think you can go wrong with any of the 3 top machines anymore.
They do sound a little different, and the way they operate is a little different, but the tech has now reached the point where it's pretty much down to personal choice rather than something more physical.
Something else that is coming though is Helix Native as a full featured app for Win and OS. A Helix in your computer. Alone it is going to cost quite a lot, BUT if you have a Hardware Helix already, it's only going to be $99 - and apparently it will be a multi-machine licence so you can have it on your desktop and lappie too.
The Helix is already awesome at doing re-amping, but if I can do that all in the PC, then that will be awesome.