I have had similar problems with my SRT. The power loss was unpredictable, and when it went out I felt like I was on a bicycle...no power at all. Living here in Phoenix, the heat is certainly an aggravating factor. I just replaced my IC pump with a stock replacement....bought from Rob at Needswings. My car just turned 18K on the odometer, but sure enough it was the pump. Since I was doing this I took the opportunity to flush the entire cooling system and replacing the factory coolant with Zerex G05. I also added one bottle (a pint I believe) of Water Wetter, obtained from the local Checker Auto for about $8.00. I also installed one of Needswings isolation kits, which is a 10 minute modification. Its been 3 weeks now, with daytime high temps way above 100 degrees. No power losses at all, and the car is running great!!

For the record I too was concerned that it was a bad IAT sensor, but it appears I was wrong. It is amazing what just a new pump will do to fix
the problems. I didn't pick the Johnson pump since I was worried that it's higher flow rate might increase internal pressure and cause the actual intercooler under teh SC to spring a leak...probably too cautious on my part.

Good luck. I would suggest you try these mods first (total cost was under $225 including new coolant and Water Wetter) before selling a GREAT car.
It goes like stink, and is a blast to drive.

John