Welcome to the forum.  A recent post from a new memeber tells it all.  You will not unhappy with Tikka.

my question is whether or not it is worth the extra money to invest in the stainless steel model over the regular blued model,

and if there are any differences as far as performance is concerned outside of survivability.

Welcome, Tim. To me, it's worth it to have the stainless model, just for the “survivability”.

Difference in performance?……………..no.

I might be the new owner mentioned, and I have the T3 Lite SS in .308.  Great gun, and meets all of my criteria.  Extremely accurate, excellent trigger, weather resistant, light, and it is pretty and has the smoothest bolt I've ever used to boot.

I wanted stainless for rust resistance, as I've seen too many rusted barrels, and while I do my best on the upkeep, I figured may be money well spent.  I also prefer the look, but that is a more subjective issue.

I highly recommend this rifle.

I guess I'm a little late to chime in here… But I bought a T3 in stainless also (Varmint barrel). Can't complain so far!