Well, something I don't see mentioned is: What is your experience with revolvers? If you are more familiar with one type over another, that could sway your choice. Also, if you have no experience, I'd suggest getting a .22 to practice with AND one of the choices you listed.

As can be said of most "either or" scenarios we see in this world - either gun you mentioned will do the job admirably.

If this is your first big bore, I'd go with the cheaper one so you can have more money left over to buy ammo for practice with.