HI Tony,
Like Brother Phil said, they will work fine, stock, as long as you don't expect a 4-2 run. A lot of good engines came out at a time when stunt was still being ruled by the "Classic 4-2 style" enginew run, so they were cast aside when they wouldn't do that.
There are plenty of great engine guys who can get the 4-2 run out of them, and usually with plenty of power left for our purposes. But a "low" pitch prop, and a soft 2 stroke needle setting will work in most all cases. Some better than others, but all fine for "Sunday" flying.
Big Bear