They kill fine, however I greatly prefer Noslers 95gr Ballistic Tip. It penetrates well and creates a great wound channel. I think we've only caught one and that was in a big bodied WT buck at 427 yards, after it shattered the onside shoulder and spine.
I also like the 95gr NBT very much. Thanks to input from forum posts I was able to load some up with great results! This was shot out of my Sako Forester. 5 shots at 100 yards!
Like them alot here as well. Great on antelope, mule deer etc. Haven't tried the 80s. I have also heard good things on the 95 BT. There are lots of good bullets for the 243 calibers. I do like the 85 tsx though.