Seems to be a safe bet that Harry Mabs doesn't get talked about as much as the other designers.
Probably due in part that he just goes so far back in flipper pinball's history (the beginning) but hard to deny that Wayne Neyens took off like a rocket when he became the chief designer at Gottlieb after Harry left, so I think this would be the main factor. And then look what happened when Ed Krynski took the baton from Wayne! What big shoes he had to fill. And not only did he 'fill' those shoes... but did it extraordinarily well.
But I was recently talking to a friend who is working on a lot of Harry Mabs' games in a collection and he told me he was amazed at how good these games were. I personally do not own a single game he designed and really haven't even played many of them. I do remember how surprised I was when I first played the 1950 Bank a Ball he designed. Sure doesn't look like much when you see it.
More recently at the Banning show they just happened to have a Music Man. I more or less just played it because it was 'there' and more importantly, was one of the few EM's that was even playable. And I was again struck by how well the game had been designed.
These two instances and what my friend recently told me, lends me to believe his games are a lot better than most people are even aware of, including myself.