I recently got three quotes on replacing my ac unit. Two of my quotes were pretty much the same in price. The Trane (Xr11 2.5 ton), and the American Standard(Allegiance 11 2.0 ton) were both around $1830. I was also quoted a Lennox 10acc for about $1650. I don't know a lot about these things, so I wanted some advice on which brand is better, and are the prices I was quoted resonable. Can someone please advise?