Just did my first day at High Plains Raceway near Denver, CO this past weekend and had a blast. The elevation changes really add an extra layer of fun to the track.
My car was on RE71R 245/45/17 tires. No mods other than wheel/tires and high temp brake fluid (RBF 600 stock brake pads). I do have camber plates, but was on stock alignment. Unfortunately my car hit limp mode during my fourth session (ambient temps around 65F) but brakes held up throughout the day.
The track was crowded enough that I only really got 3 clean laps the whole day, but I managed a 2:08.
With a more aggressive alignment and better driving, I think a 2:06 should be possible!