We're 2 years in with a Carrier Infinity. So far, so good. We wanted the more efficient fan and the better thermostat controller.

I like its ability to run the a/c slow so it will dehumidify without cooling too much below the target temperature. Since we've gone to this system, I haven't had to manually drop the temp on high humidity/low temperature days (ie, temps in the 75 degree range but 90% humidity) in the summer. Our old system would shut down because it hit the target temp, but the house would still be uncomfortable. So we'd knock it down (and then leave it there) a couple degrees to get more dehumidifying.