I've been very impressed with what I have read on Rheem's mod system. I've obtained four quotes to replace my furnace and A/C and have been leaning toward the mod. Two are Rheem dealers, one of which also carries other brands. Two are not Rheem dealers. Three of the four have made comments to me the Rheem "is okay", but the modulating furnace is prone to be 'temperamental' and often has problems modulating, thus often results in the furnace running at 100% and/or service problems. They suggest it is a historical problem in 'communication' between the furnace and the T-stat. They also suggested Rheem factory support may not be all that good. I didn't have the impression they were just saying this for competition sake, as one was even a Rheem dealer. Because I heard this from three of four reputable dealers it concerns me. Can anyone offer any support one way or the other on what these guys are telling me about Rheem's mod? Thanks!