We waited 3 years after opening to ride this, because the lines were always so crazy.
Last Summer, we were in the park on a Friday morning and there was nobody in line, so our wait was 5 minutes. My kids (who all LOVE the Finding Nemo movie, btw) were ages 5, 9, 12, and 18. Nobody "hated" it, but none of them particularly liked it, either. It was long and boring, IMHO. We love everything else at DLR - this is seriously the first ride any of my kids have ever walked off of with an attitude kind of like, "Hmm, that was lame". I liked the sub ride when I was very little, but I had to agree with them on this. We'll likely never take time out to go on it again.