The .243 is a fine deer cartridge IMO, but you either love it or hate it. There are plenty who like to kick it in the ribs and trash it, but I love it. I've used it for years, as have several friends. We've never been disappointed. Use deer bullets and not varmint bullets, and it kills well.
I've settled on the Sierra 100 grain Pro Hunter. I've only recovered one, and it was a hard quartering toward shot at 40 yards that hit a big bodied buck in the shoulder, destroyed it and I found it perfectly mushrooomed under the hide at the last rib on the opposite side. The 100 grain Gamekings have been good as well.
A friend has loaded the 100 grain Remington CoreLokt bullets for years and I'm tired of dragging his deer for him.
I'm gonna try the newer 95 grain Nosler Ballistic Tip, which has a very thick jacket, unlike the older ones. I've heard great things about it.
It's a reloader friendly cartridge IMO, and several powders work well, but H 4350 is your best friend.