I had the same dilemma and ended up getting the CB's. You can get a blended set with your higher irons MB for the same price. I wanted all mine the same so I ended up with the CB's just in case I couldn't I couldn't consistently hit the long irons in the MB's.

Thanks John, how would I go about getting a mixed set??

Definitely look into a mixed set. Any Titleist retailer should be able to order them for you no problem. It is up to you to decide what set make up you want, I think anything is possible. Off the top of my head I am not sure how the lofts match up (should be pretty close) but you can always order them bent a few degrees to match up better.

Before you drop the money though, I recommend getting fitted so then you'll have that added "made for me" confidence factor.

After my fitting down at TPI, I ordered a mixed set. I went with 712 CB 3-5 and 712 MB 6-pw and did not like it at all. The only reason I went with that setup is b/c I was playing a mixed set in my MPs and wanted a little more forgiveness in my long irons. 

To be honest, I did not like the feel or the turf interaction of the CBs and I went to a full MB 3-pw set. I like this setup much better and the forgiveness of CB vs MB is not that much. If you mishit a long iron, it doesn't matter too much if it's an MB or a CB. 

I would recommend a combo set.  3-5 or 6 CB, the rest MB.

Nick,

I was in the same boat several years ago, was playing DCI's, and I hit both the CB and MB irons and settled out on the 690CB.  I have found that I can work the ball well with the CB.  You have to put your range time in but I have been so very pleased the CB.  So much of it how it feels and how the iron looks at address to you.  One thing that I love about the CB is the thin lines when you look down it is like you are looking at a blade and when you hit them on the screws..  second best feeling I have ever felt.. LOL!  Good luck with it, you will not be disappointed whichever one you go with.

CBS

I would say go get fitted and make sure to put the two head to head in the fitting process. Unless the CB's are the overwhelming winner though, I would definitely go with the MB's. You can't beat the feel of the MB's.

I just bought a set of the MB's last week. I went in to a fitting almost certain I would leave with MP-69's, but the MB's beat out everything about 10 times in a row. Played one round with them so far and hit them way better than my previous irons (CCi forged). Very solid, low profile, great turf interaction.  

You can obviously work the ball with these better than anything else. If you are working on your game a lot, you will have no problem at all hitting even the long irons. They are way more forgiving than blades of the past. The feedback you get is second to none with these, which will help you improve your ball striking even more, especially if you spend a good amount of time at the range. 

Thanks everyone. I went and got them fitted and I went with the MB set. I didn't find them to hard to hit. I thought the CB and MB's were very similar feel wise.  I also went with the MB set because they look so classic. I love it.