I did try an ISO burn with Decrypter, but it was a "backup test" of a navigation disc for a co-worker. The data all seemed fine, but the Nav player didn't recognize it. The original was burned using PTP, whereas all (I believe) burners nowadays use OTP. So that might have been an issue too.
Anyway, make sure you check for -ROM setting in Decrpyter first before burning.
I did try a burn with my LG 4163B and the start of the second layer had some pauses depending on which standalone was playing it. But the first layer scans were all similar to each other, which leads me to believe it's media dependent. For some reason, my BenQ 1620 reads the second layer with more errors, and it's consistently across all discs too, whereas the LiteOn reads them fine.