Steel -
I'm really liking those grips you got there. Where did you get them if you don't mind me asking?
To the OP, I love my Defender in 45 ACP, but it can be a bit to handle unless you are in the right frame of mind. I'm 6'3" and 260 lbs and it can wear you out. I'd really really love to have a New Agent or Defender in 9mm though. Compare ammo prices and you will know what I mean. Oh, and plan on getting that extractor tuned. Those darn 45 spent shell casing hitting you in the forehead can really hurt sometimes. Be sure to have a hat on when you shoot it.
Considering you are sort of straying away from what a true 1911 is anyway with a 3" barrel, going the next step with a 9mm ain't that big a deal. Heck get one of each if you gotta have a 45. For that matter, get a 5" 45 and a Defender in 9mm. I ain't made of money either but save you pocket change and it can happen.
Good luck.