I used to be a .243 basher, but no more.
I came up in the .30 cal/180 gr and up school for deer, and the mantra of the clan was that the .243 was a "ground hog rifle."
Ironically,my dad, who was an elder in the basher community, in his later years, bought a .243, for ground hog shooting. He found it kicked little and shot it well, so he loaded it with 100 gr slugs, and started hitting and killing deer consistently.
After his death, the rifle came to me, and bamaboy and I have killed several with it. The boy took his first buck at a lasered 260 yds with his grandad's rifle. And I have seen more dynamic DRT kills with that rifle than any other.
I liked the caliber so much that I sprung for an odd old mannlicher stocked Mossberg 810M .243 and have killed a couple more , including a nifty 80 yd neck shot last winter on a 7 pt.
After we shot up Dad's supply of 100 gr Remingtons, I started loading 100 gr Partitions. Dad's Savage shoots them well, the Mossberg not so much, but all still practical deer loads.
You won't regret a .243 on deer with the right ammo.