I also recently upgraded from the 1348 to 3541LS. I also opted for the 3541LS over the 3530 because of the total length when collapsed (important for stuffing into the travel bags I happen to own). That was also the reason I got the 1348 originally, vs. the 1345.
The 3541LS is quite a bit shorter than the 1348 when extended. Not an issue for me, just FYI.
I like the new base plate, particularly the screw that can be used to help keep a tripod head (e.g., a ballhead) in place. Previously I was always having issues with the ballhead periodically rotating loose.
Minor criticisms:
- The leg locks on my 3541LS operate less smoothly than my previous 1348 and my Basalt 1297 (which I still have). They do lock securely, but do not operate as smoothly. Maybe they will loosen up in time.
- Gitzo switched to using a different hex key system for securing the base plate, adjusting the leg tensioning, etc. Why? IMO the new system is harder to use than the old one.
- Why does the tripod head retaining screw use a smaller/different hex key than the other adjustable mechanisms? Is this really necessary? (Why make the photographer remember and carry two things instead of one?)