I owned the Lone Peak 2.5s. I enjoyed the cushioning and roominess of Altra's moderately cushioned trail shoe (falling between the less cushioned Superior and the maximally cushioned Olympus). But there was too much of a good thing in the Lone Peak 2.5 version -- the upper was a little too loose and roomy, causing a lot of foot sliding on rocks and downhills resulting in black nails and blisters.
The Lone Peak 3.0 is a massive improvement in my view. It is a much more form fitting upper, providing plenty of foot splay and comfort at the same time. I found that my foot didn't move around much and the tension of the laces were just about perfect. The laces are a bit too short, but they stay tied.
The one drawback to the shoes is the insole definitely slid around when I ran through water on a hot and sweaty day. The water drained super well, but once there is a layer of moisture, the insole doesn't want to stay in place. Dominick Layfield on Road Trail Run had the same issue with his 3.0s, but addressed it by crazy gluing the insole down. I haven't tried it yet, but intend to do so the next time I expect to be running in wet shoes.
Otherwise, I find them a great all around trail shoe in the 3.0 version. Great rubber grip, cushioned enough while still preserving enough ground feel, not too heavy (but certainly not light), pretty good at draining out after a dunk, mildly breathable so my feet don't get super hot. The durability seems pretty good for me on the trails in the DC area -- no abnormal wear is visible at 60 miles.
As Dominick writes, the newest 3.5 version is about to get released with what sounds like minor changes. Given that my first pair of 3.0s has another 250+ miles left on them hopefully and I have a back up pair that I currently use in the gym, I'm not even sure I'll have a need for another pair before they release the 4.0 version! But the 3.5 release will certainly mean a lot of good discounts on the 3.0 -- I just snagged a pair of Torin 2.5s for $68 for a model which doesn't seem to have changed much in the 3.0 version.