Just got my 16" Alpina's back from Union Rim. Looks like a good job. I won't be mounting them until the spring so this is just a report on the service and the appearance of the job.
The job included straightening, grinding, sandblasting, powder-coating (2 colours) and clear coat. When I dropped them off I had a quote already from previous emailing with John. He pointed out right away that there was a visible bend in one (I hadn't even noticed it before). He said any bends would add $50 per rim for straightening. When he did eventually find 2 other bends, he phoned me right away to notify me.
With the exception of one rim having a slightly imperfect masking between the silver and black, it looks like an excellent job. And the service was very good. It was about a 3-week turnaround - but I had told him there was no rush as I wouldn't be running them until the spring.
A season of running them will tell more of the story I guess.