I have a Arca/Swiss B-1 Ballhead and the comparable Kirk Ballhead. I love both of these ballheads and use them as platforms for eveything from my G2 Contax though my Bolex Rex 5 with Norton Animation Motor (the 8x10 Wehman is a lightweight compared to the Bolex).
You can see a couple of pictures in my APUG Gallery of my Arca/Swiss ballhead supporting my Wehman 8x10 view camera.
I too was a pan and tilt man for many years and when the first carbon fibre tripod by Gitzo was launched I decided to invest in it after doing a review of a number of tripods including the Gitzo for a UK magazine. At the same time I decided to go for the Gitzo 1376 ball and socket head and within weeks wished I had taken that step years before. The ball and socket is quick, light and very solid and I use 35mm medium format and 5 x 4 on it. I have a friend who has the Arca and it is also excellent.
It seems the consensus is on going with ball and socket!
The reason I like the Velbon is it also has an extremely simple and quick 'twist-lock' system for the legs and a splittable centre column so you can use it at a very low height (17cm), with a maximum height of 1.2m. It collapses down to 34cm in length. My priority is on saving weight and bulk, because a lot of the time I cycle to locations with all my gear in a backpack, so a tripod that folds down to 34cm in length, with a compact b&s head is going to be ideal!
Thanks again everyone, the Velbon Ultra Luxi SF it is!
Anáil nathrach, ortha bháis is beatha, do chéal déanaimh.