Mainstream Lafayette, CO (bad compared to Blitz, and they closed.)
This paintball arena is AWESOME! The staff is really cool. The manager always asked me how the games were going if he was around when I took a break. REALLY cool people run this place. The refs are fair, and when everyone is ready to play, the refs say "So, what kind of game to you want to play?" Bottom line is, they let you pick your games. The staff can also help you with marker trouble and are very nice and accommodating about it. My favorite is the scenario field. With crate stacks, bunkers, a bus, some trailers, and a helo, it offers a wide variety of cover and makes for a really fun game, even with large teams. They also have a few other fields like Hyperball and Xball.
Their prices are sweet, with normal CO2 refill prices, and a $12 entrance fee if you use their paint. Bring your own paint, and it costs $6 more. I suggest using their paint. It is the cheapest in the state that I've seen, and since I don't shoot a lot of rounds, my friends and I can share a case for a whole day, making it VERY inexpensive. I don't know their marker prices because I have my own Tippmann A5, but it seems reasonable, and the CO2 refills on their markers is included in the rental fee.
I highly recommend visiting this arena. It is easy to get to, and an awesome place to play. I will definitely keep going here for my paintball experience.