I had one of the 209x45 barrels. Awesome little barrel and it shot well. However, I walked past a stainless 209x50 barrel on a stainless G2 receiver and just had to have it.
I sold the .45 to a buddy. Its done well for him so far. It is a super lightweight, but the recoil was not objectionable.
As I said earlier, I replaced the .45 with the 209x50. I love this set up. Great carrying rifle. I've been shooting 100 gr. of Pyrodex and also some 80 gr. loads of BH209. Recoil has been very, very tolerable. And there are so many other bullet choices for .50.
My hunting load this eyar was 2 50 gr. Pyrodex Pellets with a 250 gr. bonded Shockwave in the yellow ezglide sabot.
That prints about 1.5" in mine.
The Contender ML in either 209x45 or 209x50 is one of those setups that you wonder if everyone else will ever catch on to. Go with it, you definitely will not be disappointed.
Ken