No. IMO they were awful. Sony had Symbian (?) licensed as I recall on some models, and that was the best of it. Moto, HTC, and Blackberry - ugh. My last two pre-iPhone phones (and I've used many in between Androids - every other phone until about 4 years ago) were Treo with a version of PalmOS and it basically froze anytime you looked at it funny, and a Samsung Windows Mobile device. The hardware was decent enough, but Windows Mobile deserved the death it had.

Don't even get me started on the Blackberry devices of the era. Missed the keyboard still though.