Turok: Dinosaur Hunter is still my fav. The smooth, arcade-like gameplay alongside the mystical/otherworldly atmosphere that it have with it's heavy fog, floating platforms, occasional anti-gravity water, random portals, and respawning beaming enemies give it this very unique charm that was simply not captured again in the series. The minimal slowdown (aside some of the final areas) is a bonus.
Turok 3 is easily my second fav. The fact that you can use a female Turok is one of it's strong points, but I also love the arcade-like feel to it and overall more streamlined design that makes it very easy to pick up & play. The story is great and I love the cliffhanger, and Oblivion and it's Flesh Eater horde are such awesome villains. I also liked the areas that you explore, each one have a very different atmosphere to them but all ultimately feel melancholic, like if a unknown force was pulling the strings behind everything (guess why it is called Shadow of Oblivion). I only wish that this game was also getting a HD remaster, I think it deserves it.