I own a Zero Air 26" (polycarbonate), although I think this line has been discontinued by Halliburton. As far as lightweight goes, it cannot be beat, but part of the lightness comes from lack of built-in compartmentalization options. The wheels were good but not as good as my old Rimowa Salsa. I did not like the handle at all, but I noticed they have completely revised the handle on the new models so they probably got complaints. Still, I do not think this can be beat as far as a large ultralight hardside, and I still use it when I need those specific features.

I have no experience with service or warranty.

If you find yourself in NYC, their flagship store a little east of Times Square has basically their whole lineup and the salespeople were super firiendly.

Make sure to buy on sale. They seem to be on sale all the time.