Barry,
At this point, my opinion is that the PCM 90 reverbs are better. I have only had the QU-16 for about a week so only time will tell if digging into the SMR will give me better results. Compared to the PCM 90, they sound a bit thin. The PCM has much smoother tails as well. The same goes for the Delays, I prefer my TC Electronics D-Two for the same reasons. I also like the Lexicon PCM Native as well as the Relab LX480 plugins (I use them extensively for recording).
Don’t get me wrong, I absolutely love the QU-16. The workflow is amazingly easy to learn and adjust to. I can’t say enough good things about it! Perhaps future updates will include better effects algorithms? Or even better yet, maybe the QU-16 will allow 3rd party plugins 🙂