I own a few Tikka WH rifles with Syn Stocks. Normally, plastic-injected synthetic stocks are junk, and the only real good stocks are those from McMillan, HS Precision, etc.
However, the Tikka synthetic stock (not necessarily the new T3, but the WH syn stock) is actually much nicer than syn stocks from Remington and Winchester. In fact, Remington syn stocks are the cheapest, in my experience, because they are the most flimsy. Winchesters are a bit better because the shell is thicker and also has foam injected inside.
Still, the Tikka stock is even better. I think it's because the Tikka's stock has ploy-something mixed in. The stock just feels more solid. Don't get me wrong, it's not as nice as a McMillan, or even HS, but it's better than most syn stocks.
Zachary