Not bad shooting with a 2" Hack. Seems it prefers the 357 loads. Which were you shooting in both calibers? 158gr., 125gr.? If I were you I would practice mostly with 38's, shooting at least 10 to 20 rounds of 357 with every range visit, if that is what you will carry. You won't beat up the gun with 38's and it will keep you familiar with the blast and recoil of the 357.
A steady diet of 38Spl.+P's will never harm the 605 either. But a little more expensive than 38's for practice and target shooting.
Glad your happy with your purchase.