(aka, yet another tripod head question.)
I just picked up a Gitzo 1541T compact tripod, which I love, and which holds even my heaviest gear quite solidly. Unfortunately, I can't say the same for my current ball head, so I'm going to have to bite the bullet and replace it sooner rather than later.
Having read Ben's excellent 1541T review (which convinced me to buy the 'pod in the first place) and various other comments around here and in the tripod FAQ, it looks like I probably want to go with a lightweight compact head from either Markins or RRS, or a combination of the Markins head with a RRS plate/bracket.
I'm not currently invested in any bracket/plate system worth keeping, so I'll be starting from scratch with either setup. Based on my equipment and usage, it looks like I need 1 camera plate, 1 lens plate (for the 100-400mm) and possibly an L-bracket for portrait mode. Whichever system I pick, needs to last me (besides potential new brackets for a camera upgrade) as I really don't want to have to go through this again for a long time.
So, my choices are as follows, please critique, suggest alternatives, etc as you see fit.
1 Markins Q3T ball head with lever release
1 Markins Camera plate for 60D
1 Markins Lens Plate for 100-400mm L
Total cost: $410
1 RRS BH-30 compact ball head with lever release
1 RRS base + L plate
1 RRS lens plate
Total cost: $450
1 Markins Q3T ball head
1 RRS Quick release clamp (model yet to be determined)
1 RRS base + L plate
1 RRS lens plate
Total cost: $604 (OUCH!!)
I'm leaning more towards the Q3T, either complete or combo, due to it's nice integration with the folding legs of the 1541T tripod. On the other hand, that means I either have to special-order the head without the lock-tite and/or plate (I think) or not have an L-bracket for portrait mode. (On the other, other hand, the L-bracket would interfere with the rotating LCD on my 60D, which would be annoying.)
Almost forgot - I mainly use the tripod for landscapes and low-light photos when out wandering around the city or on road trips. Primary use is with the 24-105mmL on my 60D, secondary would be either wide angle lens, occasionally the 100-400mmL. Ease of use (particularly leveling) and stability are my primary goals here.
So, sorry about the long winded post, but I'd really appreciate some feedback and advice on these options, as my previous ballhead choice was based on "hey, that's cheap, I'll get that one!"
Bonus question - If I get a RRS camera L-bracket, am I reading right that it's modular so most of the time I would only need the bottom portion, and attach the side only for portrait mode?
How well does the tripod fold over itself with the PC-30 attached? 
