Generally you may also want to look at the parts and their tolerances. You should try and find a machine that is 10x more accurate than the parts you'll be checking.
Also data acquisition, do you want to scan the part or use a touch probe? Maybe a combination?
As for customer support, my best experience has been with Zeiss. I am also very impressed by LK's strides to help users, though I don't have any of their products they seem very costumer oriented.
As for what I see with innovation, I am most impressed with IMS and Zeiss.
These are all personal opinions.