The 4 legs section version is indeed a bit easier to pack, but for the rest I would recommend the 3 leg sections:
- more rigid,
- faster to deploy and less operations to do so which can be important in cold weather
For the rest, I also find Gitzo to be excellent material, I have been shooting mostly with their GT5531s recently and believe that it is probably the most stable tripod out there, although most people would find it too heavy for field work.
Cheers,
Bernard