Free Parking, Fast lifts, no lift lines, excellent trails, great park
Less snow than surrounding mountains
I ride Keystone nearly every day, even though I work in Breckenridge. There are several reasons this is my mountain of choice. First of all, I can park for free and simply walk over to the lift. No shuttle bus, no gondola from town that stops every 30 seconds, no $25 or $33 parking. Next, the lifts are almost all high speed, and most provide access to long runs and plentiful powder (if there is snow), as well as providing a lot of vertical in a single run. Finally the overall vibe of Keystone is just flat out better. The staff is friendly, and you run into far less snootiness than you do at other resorts. Easy access, superior terrain (if you know where you're going) and a great vibe makes Keystone an easy choice for me every time.