We will find good and bad in anything. An engine can go a mile, or a million miles. These are very old hunks of cast iron. We have no idea of the past that they have experienced. The best rebuilder in the world can make an engine that can blow the next day. It is all up to a piece of metal.
We also have to take into consideration, people are all different. There are people that are as honest as the day is long, and others that will rip you off and not lose a minutes sleep.
I had a generator rebuilt. The person was very well recommended. The generator never worked. I finally brought it back to him. He had it 5 months. I never harassed him. I did call one time, he said he was too busy to get to it, but he would. I called 3 months later and said I was just going to pick it up and get another. When I went to the shop to pick it up, he was not there. I was to pay $60 for the work done. When I opened the box, he had ground off all the bolts and screws, grinding into the case, cut all the wires, removed all the brand new parts that were in it, and I got an anchor. This was a very obvious act.
While other people swear by him.
So you asked a question, and you got input. Some good, some not so good.
It is such an important question. I am glad you asked our opinion.
I hope you find the perfect fit, and you have many wonderful miles enjoying it.