I'll put it this way. What lifted my eyes on this stuff was an old friend of mine who played basketball for Wooldridge at KSU. He told me of the benefits he got. I also had an acquaintance who played under Snyder in the early 2000s, and he made no secret of how he could afford the things in his house. I figured if a program as bad as Wooldridge's and a coach as classy as Bill Snyder was perceived to be, can be cheaters, then anybody can. Then I moved to Lawrence and sure enough saw the same. I also knew people at Mizzou and Nebraska who could vouch for the same at their programs. I'm pretty sure it goes on everywhere. The only player at KU over the years who I'm absolutely sure never took money, was Wayne Simien.
I wouldn't be confident my program was clean, no matter who my coach was. Even Beilein. Does he have a reputation of being clean? Maybe. But he has gotten plenty of recruits the last few years, who had offers to other programs that definitely do cheat. Either they really really love Michigan, or somebody is getting money to them. Beilein may be clean, and distance himself from this stuff as much as possible, but that doesn't mean his assistants are clean or that friends of the program aren't hanging around getting in these kid's ears.
This isn't something new to me that I'm saying just because KU may be in trouble. I've been talking about this stuff, and rampant steroid use(among other things) for years. If the average fan knew just what goes on behind the scenes, their heads would explode. There are cheaters who don't get caught and there are cheaters who do, then there are non-P5 schools. And some of them probably even get in on the action.
All coaches know what goes on. Some of them are directly involved, some take the "I'm gonna look over here while you do your thing" approach, and others try to avoid it as much as possible while knowing that they inevitably can't stop everything, so they look the other way when they stumble on things. Then they self report minor things to divert attention and appear clean. I'd be surprised if anybody is completely clean.