I have gotten quotes for the T135 and SQ145, the quotes are not that much different. Looking at the specs of these 2 heat pumps, I see that the T145 is rated higher for BTUs (132k vs 121k) than the SQ145 and the SQ145 is more efficient and quieter than the T135. The cost differential is about $320. Also, I live in the Boston area and I am still not completely sure if a heat pump will help me with extending the season.