Besides the comfort issue, there is also the reliability issue, especially on ASA. I only worry about making it to my destination when I am on a CRJ (barbie jet). If I know I am on a 700 or 900 I don't worry.
BTW, before someone feels the need to correct me and tell me ASA is now Expressjet, I will continue to call it ASA until they prove otherwise. I fly Expressjet on CO (UA) flights all the time, and have never had a problem.
I try to book away from both the CRJ and ASA, but it is sometimes just not possible.
Bets on whether ASA will have air conditioning on the CRJ this summer?