The engine itself: parts seemed of good quality and were easy to assemble until I got to the over thought, over designed water pump. Why not just an impeller in a housing like every car? The carburetor was also horrible to install. The engine didn't come with instructions, you have to download and print them. There are misleading images, and the English instructions contradict the Chinese at times. I had to tear down several times and change screws and parts. Misleading images in both also. No oiling system is just plain stupid. Why should I have to tear down a whole engine because it needs oil?? The screws on the distributor cap feel like they're welded in, they are stripped now, the hall sensor is not installed and no instructions on that. I'm still not sure what I'm going to do there.
The bundle: I got the bundle with base and starter kit, no battery, no info about the battery connector type needed, the wires on the CDI are stretched to the limit going thru the base (I hope, because it doesn't come with a screw to attach the ground, so hopefully I can make it work when I get one). It just may not reach. Coolant lines need lubed and heated to attach (come on, just a little bigger??) The instructions for the fuel tank installation are totally lost in translation. If this thing eventually runs I will be very happy, if not, not surprised.
And for $650 you couldn't POSSIBLY include an air cleaner to protect it??