I have the twin to yours (except mine came magnaported) -- I think you're really gonna like it.
Here’s my experience with the .475 (one of my favorite calibers, especially in the FA revolver)
I bought my 6” (ported Std Round Bbl) FA 757 in August of 2007. I found the gun on Guns America. After I had committed to buy it I had a overwhelming surge of uncertainty/trepidation. As it turned out, I haven’t owned a gun that I enjoy(ed) more (equally yes, more no). I shoot, on average, 4 times a week. The FA 475 is shot every time I go out. I have a little over 12,000 rounds thru this gun to date. Due to the cost of components, I don’t shoot as many rounds per outing as I did when I first bought it but still run 20 to 30 rounds per outing, mostly 400gr at 1,100 fps. This load level is actually comfortable for me to shoot and allows me to maintain the hard earned skill level developed over the last year and a half.
Moving up the power ladder, it is significantly more difficult (at least for me) to shoot 420gr bullets at 1,300 fps. Fatigue sets in quickly with the concentration and physical effort required to control these loads. You can actually hurt yourself if you are not an experienced shooter, or if you lose concentration. I’ll shoot 3 to 5 rounds per outing and up the number as we get closer to hunting season. Recoil isn’t painful (unless you hit yourself in the head), but it is heavy/fast and you have to maintain a good solid grip on the revolver. You don’t want the gun “rolling” in your hand or any slippage for that matter – too many sharp edges on the FAs. I could easily get along with 400s at 1,100 fps for anything I might use the 475 on -- but can’t get over the feeling that those 420s at 1,300 might give me a needed edge in the field (southeast end of a northbound elk for example) .
I’ve settled on the two loads mentioned above, the lighter one for plinking, rolling cans, rock busting, varmint shooting and every day use, and the heavy one strictly for hunting. For all intents and purposes they shoot the same point of impact out to 50 yards.
My old eyes have trouble picking up Black on Black sights in low light or against a dark background, so I really like FAs fiber optic front sights (especially the green version).
It's hard to explain the high degree of visual satifaction I get shooting cans, plastic containers, milk jugs and rocks with the .475 -- that big bullet really moves stuff around.
Hope you enjoy yours as much as I have mine -- I'll be heading out in a couple of hours to send a few down range.
Paul