Oddly enough there are decent cats in prospect lake and quail lake, would not eat them from either place but I have seen pics of 20+" cats from there. If you really want cats the closest decent cat fishing is Pueblo reservoir in my opinion.
pueblo is good but you need a boat to get to the good spots, I am not a cat guy but I have caught nice ones on lures while fishing for walleyes or bass. the last one I caught was in a walleye tournament with a lot of walleye boats around and it took us about 300 yds. from where it was hooked, when we got it in the net it weighed 14 lbs, I held it up for a photo then dropped it back in. about 4 hours later at weigh in, a guy on the bank yelled at me, your the guy that caught that 24 lb cat aren't you. They sure grow fast in pueblo