Short and sweet, I've only played the NES MGS so I don't know how the other games play but this game plays good and looks great. Controls are easy to master and sneaking around and squeezing info out of the guards before you put a knife in there chest is always fun. Since its a small map the challenges go real quick. Definitely a renter.
I'll get this out of the way first, yes it helped that I played this through GameFly and didn't have to buy it for $30.
I've never played a MGS game before but this one definitely was good (I understand this being open world makes it different).
Gameplay was phenomenal as well as the amount of control you get for completing the mission the way you choose. Now, the rest of the review can make or break whether you enjoy the game. It's true that the first time you play the main mission you can finish it in around 1.5 to 2 hours, however, the rest of the 5 missions do give a lot of play time as well. If that's all you're going to play then it's true you'll only get around 6-8 hours out of the game for $30 (assuming you buy it at retail). If you're like me and go for the trophies, it took me more than 18 hours.
Even this can go two ways. After playing the game the first 2 or so times through you begin to memorize the movements of the guards and other patterns. It then becomes more about executing the perfect extraction rather than exploring. If you like that type of gameplay aspect then you'll get a lot of play time out of this game (or if you're a trophy hunter you'll do it), but if not then you'll most likely be relegated to the 6-8 hour playthrough.
However, as almost all of you are GameFly subscribers, you should get this game regardless since it won't be costing you $30. I finished the game in around a week and if I had bought it for $30 I would be left thinking "now what?". But with Gamefly I just mail it back and get ready for the next one.