Most are really good, but there have been issues, mostly minor.
One major though, with my Opel Senator which I had to send back. The complete rear window was deformed. Looked like someone overheated it and it shrunk.
When I mentioned the problem in the first place through email they said it were hand crafted high quality models (with low production numbers) and they wished not to replace the Opel by another sample. Thinking the defect was minor and my 'complaint' was not worth that.
Never heard back from them what their opinion was about the defect when they saw it. Couple of weeks after returning the response to my second inquiry was that it could take a couple of weeks for the returned time to travel from the storage to customer service(!?!). But then again, I assume it has arrived by now :-) still no feed back..

Am a little reluctant now ordering the BoS resin.