I have not used this bullet in the 243. BUT I HAVE in the 25, 7mm and 30 Cal's. They seem to expand fairly easily, at least initially, than only open so far.
My cousin uses them in his 300H&H, he find s them a bit "too soft". His loads are not much more than what the '06 will do.
I load the 120's for my brother and he loves them, they seem to work wonderfully.
I shot a couple deer with the 160's in my 7mag. Worked like a controlled exp bullet, I have yet to recover one.
Based on that, I would not hesitate on trying them and having piece of mind that they will do what I am asking of them.
If you want one I KNOW about, try the 100Gr Interlock in SP or RN from Hornady. Nice, relyable performance.
Good luck,
CW