I finished Twin Snakes within two weeks of picking up an overpriced copy and thoroughly enjoyed the MGS2 graphical engine updates. The MGS2 game engine does make the game easier to play in addition to being smoother, but it does undo certain challenging game design aspects of the original thanks to the FPS shooting ability. Surveillance cameras and remote guns can be easily shot out rather than having to rely upon chaff grenades. Some boss fights are similarly changed.
The cut scenes with Neo/Snake were a bit confusing. Even though Snake is a genetic clone of Big Boss (a very human soldier with no super powers), that doesn't exactly make him a Cyborg Ninja, faster than a speeding bullet, able to leap air to air missiles.
But hey, not too much point in doing a carbon copy remake of a game with just an updated graphical engine. Even Resident Evil, the other great remake to find its way to the GC, made significant changes along with the new visuals.
The visuals from the original, ten years later, are officially dated, and even the controls are dated (XY axis aiming, straight out of 2D shooters), but it's still a classic, although not without its share of problems.







