Chris,
I upgraded our shop in 2010 to an Ingersoll Rand 10HP dual stage compressor with a 120 gallon tank. I have three of us using air (including sanders, spray booth, WBS etc) tools and it is a great size for the smaller shops like mine.
I keep the tank pressure at about 150 PSI, and regulate that down to about 95 in the lines. The compressor is rated at 35 CFM at 175 PSI, so at the lower regulated pressure it is a higher CFM that is can supply, and should work for you as well.
I cant say enough how much I love that compressor. it replaced two 5 HP units I was using (with 60 gallon and 80 gallon tanks) that seemed to run all the time. The new one runs much less frequently. I think air sanders still use the most air out of the tools I run.. that and if I am spraying for a few hours at a time. Im on the 5th year so far of daily use and it is awesome. It will still run often with two sanders going, but it is rated for 100% duty cycle. I keep mine in a separate room from the shop to keep the noise down, and it gets pretty warm when running a lot during a hard days use, but you can still put your hand on the motor comfortably.
Hope that helps..