p.2 #2 · Another RRS vs. Markins Ballhead Question
I have both the Markins M10 and the RRS BH-40. I use the BH-40 more because I like the more concise feel of the lever and knobs compared to the mushy feel of the Markins knobs. Just a personal preference. The Markins head is a bit smoother though.
p.2 #4 · Another RRS vs. Markins Ballhead Question
The BH-55 arrived and it is certainly smooth - but I still notice a little bit of stiction when using the 24-70 (nice w/300). Perhaps I'm just being too picky, but I would like to try a Markins someday just to compare.
p.2 #11 · Another RRS vs. Markins Ballhead Question
I've used the Markins Q20 for 4-5 years, getting it wet and also exposing it to the harshest desert conditions (wind and sand). I wipe off the sand after trips and put some more oil on it a couple times a year. It is still VERY smooth and working great. The biggest gear I've used is the 300/2.8 and a DS1 mark 3. It handles that load without a problem.
I cannot speak for the alternative: no experience.