Is there a big difference in reliablilty between the Tecumseh OVH engive and the Tecumseh Snow King L head?
I don't know but the Tecumseh flat head is a great motor. Plenty of 30 year old plus motors still going strong today. Modern motors are more efficient and make more power with less displacement but they probably will not see the longevity of the tek flat heads.
Most people are going to do whatever they want. What I find entertaining is how people justify what they do.
Some of the Tecumseh OHV engines were known to have problems with their compression release mechanisms failing too. Plus Parts are difficult to get for the OHV Tecumseh engines. I would get a newer Briggs or even a Predator engine over a Tecumseh