The only dealing I have had with the SH line of engines were the 1/8 scale on road engines (3.5cc .21cu)when were were stationed in Japan.
They were excellent motors and very powerfull and easy to use and operate.
Workmanship was excellent, bearings were very good, lasted a very long time before having to do anything to them.
And they ARE an ABC type engine so never use straight castor type of fuel. I only ran mine on synthetic.
As far as the aero engines go, I would not hesitate to get one and try it out. I do see that they use the larger Heli type head probably to aid in
cooling in high temp areas of the country.
I just might have to try one. I do have a new kit that the .37 would more than likely do nicely in.
Carl