Tripod head - Gitzo 1780QR or Acratech GV2

Hi everyone

I have a Gitzo 1550T travel tripod. It has a built in ball head but it's pretty small and no-frills (in keeping with the compact light design of the tripod).

I'd like to get a ball head that is easy to use and that offers quick release for the camera itself. It's a pain getting the camera on and off the tripod.

Has anyone used either of the above, what are the pros and cons of either in your opinion?

Many thanks.