Never used one Mike. I've done lots of panoramas over the years (I started with a Kodak Instamatic with scissors hardware based system
about 35 years ago.
No doubt a head designed for panos would help, but unless you have some very close foreground I wouldn't expect you should see much difference, but I'd love to try one to prove it to myself (or otherwise).
As for stitching issues, my experience has been that the software gets tricked up by moving objects in the FOV - ocean waves are particularly difficult - and a head won't help that. But having said that, the software is getting pretty good these days
. I used to use a lot of specialist software to do the stitching, but since CS4 and CS5 got reasonable at it that's all I've used.
Al.