On the Honda 21" mowers if you get a commercial model it comes with a GXV Honda engine in 5.5 hp. On other models you get the GCV 6.5 hp. Now the other models are cheaper than the comm. units and have more hp. But, is the GXV a much much better engine and worth the extra $$$$. What about power since the GCV is listed as having more hp. I use 21" mower exclusively and trying to make a good decision.