Summary: After a long internet search and reading other reviews I decided to buy the GT3530LSV and also bought a full Wemberley Head. There is a very small learning curve reaching the twist locks but it works wonderfully and provides rock solid support. I have taken this set up to 2 rookeries using a 500mm lens and are really impressed by the support this provides. Save yourself the pain and aggravation and just buy this tripod. You cannot go wrong.
Summary: This is really the tripod I've wanted for a long time and had to save up to purchase. It's light, flexible & durable. With my first impressions on examination and putting together.... I purchased the Bogen Half Ball. It went together very easily. Seems like it was designed to work together. (the Gitzo has been out of stock for a long time) This will definitely be the cheapest part of my setup. I am used an ol' Bogen 501 head I had on my last set of legs.
Pros: Good Stability, Lightweight, Unfolds Quickly
Summary: After taking some time to properly grasp the new Gitzo model designations, I decided that I wanted a 3 Series systematic carbon fire tripod in three sections, the latter for improved stability. To my mind the ideal tripod for my applications would be the 3530 LS, except Gitzo have none.