I'm in agreement with the majority. The recoil of the .454 is sharp, especially with the lighter, say 250 grain bullets. I have shot many rounds with a FA 83 in .44 and that is very easy going compared to the casull. I know that the 83 is a heavy .44, but still.
I've been shooting the casull for a year now and I must say that it takes some practise. I've had a couple of .44's before and they took some concentration to hit well too. I think, that as long as the gun won't make cuts on your hands etc. while shooting you'll be ok. The feeling of heavy recoil and the sound of that big round can be actually fun AS LONG AS IT DOESN'T PHYSICALLY HURT. The grip, of course, must fit your hand well.
When I was getting ready to order my FA I was on the fence whether to get a .44 or .454; I was thinking I might not be able to handle it. I took the plunge and ordered it in the original caliber and I'm quite happy with my decision. If you're fine with the recoil of a .44, you'll learn to shoot the .454 just as well if you use it often.