My brotherinlaw & sister shoot both. After some trial and error,he has the 223 shooting almost as fast as the 22-250. They're both Rem 700 Varmit rifles. With the 223,you can buy shells as cheap as 5.00 a box. The 22-250's that I saw at a local gunshop recently ran around $15 a box. The shells for the WSSM are even more expensive,even at Wallyworld!
I reckon what I'm trying to say is this...If you shoot on a budget and don't reload, the 223 will do anything that the others do. If you're a reloader,not worried about ammo costs or just want to play,buy whichever one you want.