I am also playing the 990Bs right now and am a 9 hdcp. I was fitted last week at Titleist Performance Institue. I ultimately really liked the 712CBs 5-PW and 712U 3 and 4 iron. 

I also hit the mb but I did not like the way they hit as much but they still felt better than my 990Bs. I did not like AP2 as hey had too much offset for me. 

the cb would be the closest thing. but I would look into the AP line as well!

Hi Paul,

 The CB model would be the most similar iron. My advice would be to go see your local Titleist certified fitter and hit the AP2, CB and MB to see which model feels/looks best for you and you'll get the correct shaft also.

 Chris S

Hi Paul....I'm an 8, and I used 990's too, up until last year, and then tried out some AP1's, AP2's and CB's, and went with the AP2's, and they're great.....but, the key is, go and hit any of the current Titleist's that you can get your hands on....they're all great....!!!

Try some other brands too, if you'd like.....you'll come back to try the Titleist's, and I'm sure you'll find the one's that fits you....

Good luck......have fun...!!

                                                         B.P.

Hey Paul, I believe the Titleist CB 712's would be the closest to the DCI 990's. Hope this helps!

Connor,