I bought a crate motor because it was cheaper than I could buy the parts myself.The reputable people out there are very good. I would put some hard miles on the car and see if the rings are slow to seat and seal.If oil consumption is minimal then drive it.When it gets 10k on the engine something will improve or get worse? Then,,,, take out the engine and do a true blue print hand assemble. then again,it might be something little that shows up after a few passes.
something to consider in the future is an engine vacuum pump and different oil.
how many quarts/litres of oil does the pan hold,how many quarts do you run. ( I have an 8 Qt pan and I run 7 qts)