Portable tripods often sacrifice stability, and while the Gitzo GT1545T is relatively new to the market, there haven't been any complaints about the tripod's stability like with many other smaller models. The tripod legs use the company's new Carbon eXact tubes which help to make the tripod lighter without sacrificing strength or stability--the 545T model can support up to 22 lbs yet weighs only 2.3 lbs. Outside of the carbon fiber tubing, the use of only four leg sections help enhance stability, and the tripod can still fold down to 16.7 inches. As a leg set, photographers can choose the head that offers the feature set they're looking for (Or Gitzo also pairs it with a ball head in the GK0545T-82TQD).
The stability and high capacity for that minimal 2.3 pound addition to your camera bag will cost you, though. The legs only retail for $740. As owners of older Gitzos will tell you though, you won't need a new tripod for a long time after that. If you need a lightweight tripod but have heavy gear and can't risk any reduction in stability, this Gitzo is one to consider.