Gary,
   I have less than 50 hours on my IO-540 powered ES.  I've had a few bugs
to work out (the engine wasn't new), but hot starts hasn't been one of the
issues I've had to deal with.  I can only think of one time I had a starting
problem and it was due to my inadvertantly flooding the engine.  Keep in
mind that I have an electronic ignition on one side, which advertises easier
starts.
   It was a lot of work to put that engine in my plane.  We were basically
working with no guidance from a manual at all and a lot of things had to be
custom made.  Am I glad I did it?  Yep?  Would I do it again knowing how
much time and effort it took vice just getting a new ready to install
IO-550?  I'll have to think about that one...
   Skip Slater
   N540ES