I just bought a 243 for my grandaughter last October. I had no personal experience with a 243, and I didn't want to give her an un-tested gun, so I carried it one day.
I killed two deer, one shot each, at 100 yards. Both were pass-throughs; one was DRT with a shatered shoulder bone, and one flopped about 20 yards away with a couple mushed lungs.
Cheapest Winchester SuperX 100 gr factory loads.
For this fall I'm loading some 95 gr Hornady SSTs. I've had very good performance with 140 Gr Iterlocks in my 260, but I like the plastic tip bullets better than the exposed lead tips.