I live in phoenix and am replacing a rooftop packaged unit. I've received quotes on Carrier Infinity 15(50XT0603TP) and a Carrier Performance (50VT0603TP).
Infinity system - 14.5 SEER, 11.0 EER
Performance system - 14.2 SEER, 12.0 EER.
The price difference is $. Is it worth the $ to upgrade to the Infinity system?