I own many Tikkas. Some wood/blue, but many more stainless synthetic. My wood/blue guns have yet to be taken in the field, so I can't tell you of how well the "blue" holds up.
However, generally speaking, I think that buying a stainless gun is worth the extra money for the following reasons: 1) stainless obviously resists rust better (but is not rust proof), and 2) stainless finishes do NOT require re-bluing.
My opinion is that if your gun is going to see many days of hunting then, from a maintenance standpoint, I'd spend the extra bucks for a stainless gun. However, if you are a true wood/blue lover, then maintenance is not an issue.
Zachary