I am a proponent of 230 grain 45 acp bullets. The permanent wound cavity tends to be bigger with a bigger round. Lighter bullets have a tendancy to deflect when they come in contact with bone than a heavier bullet. However, if the round can achieve the FBI standard of 12" of pentration with the 165 gr round, then you should be fine. Check with Hydroshock for the specs on the round for penetration results.
165gr and 230gr are on the opposite spectrum. Why not split it in the middle with 200gr? Personally I prefer 200gr bullets in .45ACP - this way you still get a heavy bullet, as well as a higher velocity. If you do +P you can push them out at 1,000+fps. That's some decent power!