This becomes curious to me.
I've had very stable results from Optodisc; not great, but certainly acceptable results (+R 4x only).
Prodisc has been recommended to me, also, but I've read posts here that complain the quality of Prodisc varies widely. I'm not all that confident in any of the Taiwan makers anyway, but so far the Optodiscs have treated me well enough for the price.
However, the moment I see a few coasters I'll be happy to change my mind!
Some of the Prodisc scans look quite excellent. I almost bought some, but I had only $29 free at the moment, and I had to choose between 50 or 100, so I went with a choice that had demonstrated good results.
It is entirely possible, too, that I've simply been lucky to pick up a good batch. It really is hard to tell from a sample of 150 discs.