On the stick, Jericho and Punk are about equal and blow Bret Hart away. I don't think Bret was as bad on the mic as people like to say (average at worst), but he still can't touch the other two even on his best day. And yes, I'm talking about even that tirade of a promo in 1997 or the ones he cut against America.
In the ring, they're all about equal. I'd love to break it down and look at who excels in the different categories - selling, psychology, different wrestling styles, etc. - but to tell the truth, there's not much difference between the three for me. Bret might take the cake when it comes to selling. But otherwise, it's just nitpicking and I hate trying to look at things that technical. All I know is that Bret, Punk and Jericho have a long string of good/great matches that I enjoy and that puts them about equal in the ring in my book.
Overall, I'll go with Jericho. When he's at his best, he entertains me more overall than the other two comparably.