I bought a 235 that had sat long enough for the valve stems to get gummed up with varnish. I took the head to a guy here who specializes in cylinder head repairs. He pulled all the sticking vales, reground the stems, pressure tested each combustion chamber, reground a couple valves that weren't sealing properly, and shaved the head flat for $75.
For as easy as it is to pull a head on one of these, and for as inexpensive a rebuild is, and for all the problems it solves I can't see why you would hesitate getting it fixed properly.
