i'd say it's a crap-shoot between those three. they're the "elite" catchers, but it's really up to you what order they go in. there's a significant drop after that according to most rankings/projos.
I personally list them as Irod, Lopez, Vmart but thats mostly because I'm a low risk manager and I think a one year player is always high risk. Vmart very well could be the best of the 3 this year, he's probably the good pick if you are a high risk manager.
I think VMart will be the best catcher this year, but if all the catchers are left on the board, I would take another position and try to get him in the next round or get a good value cather late in the draft.
Wow, 7th round and no catchers gone yet? I would think about maybe either starting the run with either VMart or Pudge, or go to another position, and then see if you get one of the big 3 in your 8th round pick.
I think VMart will be the best catcher also. He's one of the few catchers on the upswing. What impresses me about him is the fact that he has great K/BB, gets on base well and has good pop. He hit 38 2B in 04 so I can see him going 30 pretty easily this year. He's a career .316 hitter in the minors so as long as he shows the same discipline he did in 04, he will be one of those rare 30-100-.300 catchers.
"Think of how stupid the average person is, and realize half of them are stupider than that." ~George Carlin