From what I've read, Willie would routinely run 150 balls. He'd have exhibitions where they would advertise, "Come watch Willie run 200 balls".
Schmidt has a bunch of high runs, but from his interview, it sounds like his consistency jumped up a huge notch as a consequence of chasing Mosconi's record. He describes how he now can do multiple 100 ball runs in a day, and 200 balls runs are common, and 300 ball runs are common as well. He has more 400+ ball runs than anyone on the planet.
I think Schmidt may not have been Mosconi's speed when he started, but it sure sounds like he is now.