I ordered this for my son, who is crazy about mechanics. The engine is beautifully put together with precision components. It worked first time. It even looks great just being displayed on the shelf.
One small thing is that the instructions are not very well translated into English. Overall I'm very pleased with this purchase.
It is one of the best engines for the price. I enjoy watching it run the only downside is that the fly wheel moved witch put it out of timing just took a little bit of tinkering to get it right so for sunny tech just a heads up