I'm Springs based (actually closer to Monument) and prefer to fly out of the Springs unless UA is wanting more than $200 more vs. Denver.
One thing to note about COS, they recently offered a Premier Membership that includes the following for $200/yr:
The parking is what justified the cost for me, the rest was not important for my needs.
Here is the link for more info:
http://flycos.coloradosprings.gov/ca...embership-pass