Love these Boots
Ok, so these are my first AT boots, so I'm not an expert. But...I love them. I love them so much. They're so great on the uphill, I feel like I'm wearing mountaineering boots. I use them with Naxo NX01's and even with the heavy binding I can climb all day on these. They're also even great bootpacking or with crampons on. I thermofitted the liners at home and they're incredibly comfortable. Not for a ski boot, but for a boot, period. They're light for AT boots (especially given the trend towards heavier) and it's noticeable on longer tours. I'm significantly less tired with these than my alpine boots.
On the downhill I'm perfectly happy. I'm driving a pair of 05/06 175cm Salomon 1080 Guns with 90mm underfoot, and this boot is plenty to handle it. I ski everything I can find including steep, tight couloirs and trees and they handle it. I also use this boot at the resort and charge everything I find there and it handles it all. I am a lightweight guy (150lbs) so maybe that's why I don't need more boot? Very satisfied. I was disappointed that they discontinued this and replaced it with the Spirit 4; from what I hear that's also a good boot, but I don't think the fourth buckle was necessary at all and it adds weight.
My one gripe is that I think not only are the two lean lock positions unnecessary, but cumbersome. First, there is a difference in stiffness between then: the forward setting has a softer flex, maybe more "progressive", while the more upright setting is incredibly stiff to the point of being uncomfortable. It's like banging your shins on a post for me; perhaps a bigger skier would want something this stiff, but not me. I only use the forward lean lock position when I'm skiing; it just feels better, both with the flex and the aggressive skiing posture it allows. I'd prefer that there was only the forward, as it's too easy to accidentally put one boot in the forward and one boot in the upright, which results in a very strange feeling descent. It's easily changeable once you notice it, but if you're dropping into a tight couloir you just have to stick it out to the bottom. You learn to double-check before you ski anywhere, but it's still an annoyance.