You're starting in the right way, get as many recomendations from friends, co-workers,family,(if they like you), and go from there. Both sound like competent companies from what you have said. I don't know about either of those brands warranties, as we don't sell either of them. But more important is how you think they will take care of you after the sale, or if any problems arise. A couple of weeks ago someone posted a link to a sight that had questions you could use to help decide which contractor to go with,that is much more important than the name on the unit.imo. Good Luck with your purchase. And remember, if you're happy with the job they do, tell everyone you know, if you're not happy, tell them!