When it comes down to it, if you're going to have only one revolver, the .357 Magnum is probably the best option.
Adding another option to the expansive number of finishes available on the Desert Eagle, the Magnum Research "White Tiger" is another option for fans of this big-bore semi-auto.
Smith & Wesson reintroduced the Combat Magnum revolver with a K-frame Model 66 .357 Mag. and an L-frame Model 69 in .44 Mag. Are they the right fit for you?