If you are buying bonus buys then I think Retro Tapes/Retro Sweets has the most max wins out there. There are so many that a lot of people don't even consider it a max win because I think its max 25x the buy or something like that.
I hope that eventually with stuff like stake stats (they were talking to the guy on Eddie's kick) we can pull up games like this and see how many people have to lose for one person to hit huge and get that expected RTP.