MGS has always had absolutely spot-on gameplay, literally defining the rules of how a stealth game should be made. Pretty much every time I play something with stealth components I think 'Well, they got a lot of it right but they're missing X from MGS that'd make it so much better'. I think the hype about its stories and graphics often makes people forget that the gameplay is really, really satisfying.
Whether or not you can also get on board with the series' characters, world, and stories is what'll make the difference between you hating the series because the cutscenes, etc are always getting in the way, and absolutely loving it. I personally fall on the latter side; I think the MGS stories are retarded but ingenious. They somehow take deep issues (nuclear proliferation in MGS1, information/internet control in MGS2, the madness of war and friends becoming enemies the next day in MGS3, and a world dominated by wars between private armies and computers in MGS4) while also being OTT to the point of hilarity.