Mirth1, I like the .243 also. But I like anything that burns powder and puts bullets where I want them. Any campfire discussion of guns will lead to preferences, likes and dislikes. If you can hit them with your deer rifles, use them.
I have a ruger 77 with synthetic stock I like to use for shooting at varmints. I tricked it out with bedding, trigger work, crown, lapping, etc. Ive vaporized many a critter with it. I reload and it doesnt seem to be fussy about what goes through the barrel. I did find 2 boxes of speer 70 grain tnt varmint bullets at Gander Mountain in Utica. Boxes of 750 for $45.00 each. Great buy. I picked up 2 and my gun loves them. I have used this .243 on many a Wyoming deer hunt. Use 100 gr. Noslers. Have not recovered one to date. They all pass through and leave a marvelous hole.
I am 60% complete building a heavy varmint gun in .243. I sent a mauser action to Shaw and put a 26" barrel on it. A full 1.25" the full length. The barrel weighs 10 Lbs. Put it on a laminated stock, bedding, Timley trigger, etc. Last saturday I shot 10 rounds into a .914 hole. Take my 3 worst shots off out of the 10 and the group was .425. Im not a bench rest shooter so thats good by me. Let me know if you want to shoot it some time.
Get the gun you like, the caliber you like, what you can afford, and practic.