I have not owned one, but all of the Hunter models I have fired have been terrific guns. I am sure you will like it.
Getting 1200 fps will be no problem with that bullet, and should do most anything you could want. I like 4227 a lot and don't think that is a bad place to start. I have used it in 45 Colt and 454 Casull, but have not with a 44 mag. H110/WW296 are also good, as is 2400.
430man mentions high pressure spikes with 4227 when the gun is subjected to high temps.(I think). I don't know anything about that but maybe he will shed some light for you.
I like to load for accuracy, then see what my velocity is.
You're gonna catch hell for not posing pics, so be forewarned.
Let us know how it shoots!
Dan