Yes I have used this tripod for my ATS 80 since the summer. I pretty much love it, except for the price and getting my fingers to remember which way to turn the leg locking rings.
I was lucky to find a used one on ebay which saved me about $150. And I find that if I can condition myself to have the tripod in the same postion everytime I tighten or loosen the locks it helps my fingers to remember.
The Gitzo series generally run something like 10xx, 11xx, 12xx, 13xx, 15xx. Tripod leg diameter increases as you go up in the 1st 2 digits. In addition the carbon fiber series is referred to as the "Mountaineer".
Tripods within each series can otherwise vary in a number of ways such as number of leg sections, type of column etc. Some BF folks prefer the G1228 becasue with its 4 leg sections its collapsed length is shorter, however this means 3 more locks to deal with and extra joints that can reduce stability somewhat.
I have owned the Bogen 3001, 3011, 3221, 3246, Gitzo 1227 and Gitzo1325. The 1227 is the best one of these for scopes, The 1227 beats all of the Bogens for stability. The 1325 is better than the 1227, but somewhat heavier and bulkier.
Scope shake has always been a big issue for me. I have seen too many birders with a $1,000 scope and a crappy tripod which totallly negates the better view that they paid for. So far the 1227 is the best I have seen when size, wt and stability are considered. It still gets some wind shake, but it takes alot more wind to do so, and the magnitude of movement is aot less. Laying an arm along the scope has resulted in acceptable viewing for me, even in fairly strong winds.
One thing I would like to see is a 2 section CF tripod, but I doubt that is going to happen.