There's absolutely no doubt that I'd pick the 260 under the conditions that you indicate.
You reload, therefore ammo price is irrelevant.
You already have a 22-250 and 243, you do not have a 260.
There seems no sense in adding another firearm in a cartridge you already have.
Still happily answering to the call-sign Peetza.
The problem, as you so eloquently put it, is choice.
He is no fool who gives what he can not keep to gain what he can not lose.
-Jim Eliott, paraphrasing Philip Henry.