The zenoah is more expensive than any of the other weedie type engines in the 25cc class. It is also a good bit more powerful too. The boost port in the G-26 cylinder is what gives it such a advantage over the G-23 and other engines with tranfer ports only. I think it out run the toro by 1000 rpm give or take a little. I tached my box stock G-26 yesterday and got 8700 with a 17X8 prop.
The toro is a fine engine as long as you don't require power of the G-26