I have been really impressed with my Tikka T3 Lite. Mine is a stainless model in 30-06, with a left handed action. Yes, the trigger guard is polymer. I am un-bothered by this. It's strong, and I doubt it will ever break. The magazine is polymer, but... I use poly mags in my AR (Magpul) as well, so I don't think this is a negative. The only negative is the PRICE of extra magazines.
Go for it. They are superbly well built rifles.