Yup, that's pretty much true. Once you get to 18,000 msl, you get into class A airspace. No VFR allowed there. Now, if you live on the east coast, and over into Texas, not much of a need for much elevation. However, in much of the rest of the CONUS, a little altitude is needed for VFR/GA flights. Its a terrain avoidance issue. You won't need pressurization, but run the heater and use supplemental oxygen (the little tank and the aquarium tubing). People do it all the time. There, do I sound as opinionated and authoritative as some of the other posts (previous post excluded).
I would love to take that little Bonanza hot rod for a ride! Sure, I could probably use a 160 hp continental to get airborne, but as Clyde said, "Speed is the only reason for flying".