Well, I own an 85 combat and I'll give you my 2 cents on the subject of the sights vs those on the 75.
First off, check if you can consistently shoot good groups even at longer ranges. If your shot grouping is no good then no sight on earth can change anything about that and the only solution would be more training or just accepting the fact.
If grouping is good but your shots are consistently off to the left/right/up/below then tinkering with the sights might help you.
To be perfectly honest...when I bought my 85 combat, one of the main reasons were the adjustable sights but in retrospect I have to admit that I didn't really change anything about them. In the beginning I shot consistently about 20 cm down and right to the target center but I handled that by modifying my stance and grip...didn't touch the sights.
Also, the look of the sights is different from the standard look on the 75. Some people like it, some don't.
The 85 combat is a great handgun, but if I were you I wouldn't focus too much on the sights (no pun intended) as an argument for getting one.
Hopefully someone like Walt Sherrill who also owns a 85 Combat but has a lot more experience the myself will chime in on your posting, perhaps he'll have a different opinion.
