Fun but really long and repetitive.
Cons: Pretty much the same enemies over and over. The only difference between the enemies on different levels is that some can now throw fire or electricity at you or maybe they have more armor so it takes more hits to kill them. And it takes a ridiculously long time to get anywhere and to find the proper keys.
Overall: Buy it. Despite the ridiculous repetitive features, the game is entertaining. Definitely add Turok to your collection, but don't spend anymore than $10 or $15. Any more money, and it's not worth it.