MGS stories are fun and entertaining and sometimes actually good in my opinion. They are full of dumb, funny, and plain goofy things and thats why I like them. I feel like there's some actual substance to them and they entertain me. The same way a normal Super-Hero comic entertains me. I don't think they are fucking the Godfather or something though.
That said, it's fun to get into the story and characters the same way you get into the X-men stories and whatnot. Yet, I don't think that's an excuse when the storytelling actually gets bad, dosen't make sense by it's own internal logic, and thematically doesn't deliver.