JohnD i would take a real close look at the tauras guns they shoot decent and have a good rep. my wife has on I think modle 66 in 357 mag but 4 inch barrel.The quality is there i think it shoots better than her.
as for caliber rember that to much and not enough expireance makes shooting big bore revolvers a bitch.I love shooting my 44 mag I have a load that Almost pushes you down when you shoot it It a 8 3/8 smith.I dont like shooting 357`s or 38`s because they slap your hands.even my buddies 357 dan weason in 6 inch.Anything you plan on useing a 357 or 45 for a 44 mag will do better and to get the hang of shooting you could shoot the 44 specials.Unless you have shot a lot of pistol I would advise staying away from the 454 casaul.
Footnote if you want to shoot with out hearing protection in a hunting situation keep away from a porting job or muzzel break