Not mainstream, but in my opinion the BEST of the old tickle vid producers still out there. He used to be called Submissively Ticklish Girls, then changed to Testing For Laughs. Some years ago he quit, closed his C4S store and thought that was the end of an era.
But a few years ago he started up again with a stream website for only 7 bucks a month to view his content masked as a so called "reality show" (very smart idea to not get flagged advertising on youtube). Usually has something new every few months. He has got some of the classic content there as well. Haven't joined his site in a while, so not sure what's new since I last went over.