I think it really boils down to what you like and your budget. This mic is a tad too bright for me, and if you get off axis, you're in trouble. I like the smoother sound of the RE20, and it's off axis response is "More Forgiving." The Heil PR40 is a great sound, a little fuller and brighter as well, and like the Sennheiser MD 421-II, it too is not forgiving for off axis response.

A big surprise for me, when compared to the EV RE20 was the Rode "ProCaster." To me it sounds like a cross between the EV RE20 and the Heil PR40, but it's off axis response rivals the RE20, which to me is a big plus. Also, the price is very attractive at around $230US, when compared to $450US for the RE20. I've seen a whole ProCaster package for $327US, which includes the ProCaster, it's shock mount and scissor boom.

Here's an audio file comparing the RE20 to the ProCaster: Click Here

Again, it really boils to to your personal preferences and budget.