What a weird beast this is.
First off, TRON: EVOLUTION is definitely worth it if you're itching to return to the Grid from TRON: LEGACY. They really did a good job depicting the black and neon world of that movie; the game's got high production values, it looks and sounds great, and going back there is really pretty fun. Plus, there's time spent in both the light tank and lightcycle. Can't beat that.
On the flipside, there's the single-player combat. It's kind of a funny experience playing this game, because it doesn't take long to figure out where you've seen this before: Assassin's Creed. You're running around the Grid, scurrying up (and across) walls, and doing all of this strange parkour stuff. It's not that that's strange, per se, just that it takes some effort. The camera's pretty awkward here, and it's very easy to miss the big jump and fall into the abyss. I derezzed a lot during these segments. A lot. Doesn't work so well as a platformer. I like the fighting (though it does get repetitive), just not so much Spider-Man.
It's not a bad game. Far from it. But it does get frustrating, at least for me. I had a lot of fun in the lightcycle, and there is the occasional thrill of pulling off a harried bit of free-running. I would be disappointed if I'd paid full-price for this; but as a discount title, it'e not bad. Although I don't see much in the way of replay value.
6/10