I owned an AC and went to a Mk111 in august.I switched over most of the components as my AC was upspec on the Mk111 comp i bought.
The biggest differences are:
- pedalling, the mk111 pedals extremely well in any terrain, the Ac used to biopace and bob a fair bit especially over rougher terrain.
The tracking and handling is quicker and more responsive on the mk111, it feels a little more stable, due to a lower bottom bracket?lower center of gravity.
riding a down hill course they're fairly well matched untill it gets big, the AC has the extra travel and probably better frameset to cope with bigger dropoff's, but since your talking all mountain it won't really apply.If a fair bit of downhill is your secret desire the Ac is the choice.... until you try a sunday.
the weight's are similar with the Mk111 a little lighter (2 pounds for me)
climbing is much easier on the MK111, the suspension works really well to hold traction and absorb bumps at the same time, the front end doesn't wander around as much as the AC on the steep stuff.
the suspension on the MK111 is purely superb, responsive , plush, an eye opener to see how well it works. The Ac does the job, funilly enough not as plush, no comparison really.
The Ac was a great bike and served me very well over the years and it will eventually be built up more as downhill only bike,but it won't see the light of day as a trailbike again while i have a MK111.
