I'm now on my third pair of Ions, having worn out the previous two pairs. I ride about 40-50 days a season in a mix of backcountry, resort riding, and terrain park.
I love the Ions because of:
1. Incredible comfort
2. Light weight plus durability
3. Burton's lacing system *rocks*
I was initially worried about the lacing system, but it held up perfectly through all of last season for me. The speed and adjustability are amazing, will never go back to old-fashioned laces.
The only thing I'd point out is that these boots have a medium flex to them. If you need an ultra-stiff boot (you know who you are), then look to something like a Driver X. (Which I also have, and which also rock.)