CO will be cheaper.

SOCAL will offer a wide range of operating environments within ASEL range...coastal, mountain, desert, IMC. You can get high density alt in the desert or at Big Bear. The only thing you won't get much of is ice, but ASEL trainers can't fly in ice anyway.

The biggest factor favoring SOCAL is the high traffic density and ATC coordination required. If you are going to be a professional pilot, may as well jump right into the class B.

Also the cost advantage in CO will be offset by weather no-fly days, so your training might drag out longer. Springs is often turbulent as hell, I imagine that would be either no-fly for ASEL or sucky...hard to maintain PTS standards in a rotor cloud.