Losmandy GM8, GPDX or mount for astrophoto?

I just purchased a Vixen 140 NA refractor. I currently have a Televue Equatorial Mount but I don't think the tracking motor (one axis) is accurate enough for astrophotography. So, I think I'll sell the Genesis and Televue setup and replace with a solid mount. So, which mount would really be best. I assume the GM8. I've really not considered the new CG5 because I really couldn't stand the old CG5. Are there mounts I'm missing and should consider? I don't really want to spend more than $1,500.

Thanks,

Don

There is a well known large dealer who has Celestron CI-700 mounts (much like a G11 in capacity etc) at the non ASTROMOMICal price of $1295.00. Might we worth a look...