I love my Rugers... But the Pre-64 Winchesters are special... You can always buy a new ruger... Pre-64 Winchesters aren't a dime a dozen, especially rifles in good shape..
I will say the metallurgy is a non issue as the post War winchesters all benefited from the advances made in metallurgy during WWII... Both rifles are strong... So don't let that aspect affect your decision making..