I use TAC Air every time I fly into the Denver area. Terrific service for a short or long stay. Be wary of other FBOs that will try to marshall you in as you taxi down the long taxiway towards TAC Air.
Returned this past weekend and got the same great service I previously received. They were also very responsive to my email requests. Overnight tiedown is still $10. Weekend fuel discount now only 50 cents, however.