I am building one because it is about the same price to build one as it is to buy a used one with 130,000 miles on it. The biggest problem with these engines is the bearings getting washed out and they start to knock. If I can start with new bearings I expect to get a lot more miles out of it. I have another vehicle to drive, so there is no reason not to build it. It is also a great opportunity to teach my 12 year old son how an engine works and how to fix it.