Thanks for reporting back, Peter, a thread without a conclusion doesn't help people nearly as much as one that demonstrates a solution.
The OHC Hondas are "residential", not "commercial" like the OHV ones, but I think they generally run about as well for their perhaps shorter and less trouble-free lives. The performance you have described sounds like what I would expect, and what I am accustomed to getting from OHV ones.
The chondas seem to have a couple of small design weaknesses that are rather easily fixed if they give trouble (and I think most of them don't give trouble). The fix typically consists of replacing the inferior component with a genuine Honda one, which in most cases fits perfectly. I've seen worn out parts from chondas that were properly made to full OHV Honda specifications, but were very, very severely worn. This is from engines that did not show signs of abuse, which suggests the chonda engines they came from lasted just as remarkably long as OHV Hondas typically can. Of course I've seen reports here of other chondas that had serious early problems due to those few inferior components giving trouble - and which were restored to excellence by fitting a Honda part in place of the defective one.
If your purpose is residential, and you watch for the problems that sometimes occur with OHC Hondas (e.g. jumped timing, exhaust valve guide moved out of position, and oil leaks from governor paddle shaft) you are likely to be well satisfied by a very smooth, easy-starting and efficient engine.
