Had an engine built for my truck some years ago. I doubt I will use them again. The customer service, attention to detail, and response is not good. They are smooth talking but got the feeling that they are trying to up sell you things and cutting corners here and there. In the end, I got a strong working engine but ran into too many snags along the way.
They forgot an oil plug at the rear of the block, luckily I noticed it before I bolted up the transmission. That would have been messy.
Got talked into porting the exhaust manifold, but they took so much material off that my headers would not seal. Had to take my truck to another shop that modified the headers and made custom gaskets for it. When I complained about it, they flatly denied doing anything wrong.
The engine has had oil leaks from the beginning. Even after having them tighten things up as recommended. They are minor leaks but still annoying.
I got a sneak peek at their garage and assembly area, and all I saw was a bunch of teenagers, nobody I would consider an experienced machinist.
They seem overwhelmed with business, and I know of other people that had good experiences, but I would say it is hit and miss and there has to better options than this place.