Colt .45 wheel guns are pretty intimidating, but when the 1911 came on the scene everyone opted for the semi over the wheel. I own both, and find the 1911 more accurate with the slower .45 round.
No one really makes an affordable .45 wheel gun any more, and the .357 fits the bill for more pistol owners - it has the stopping power, plus it's dual purpose (it fires the .38 round as well).