Metal Gear Solid vs. Splinter Cell

So we had a nice long argument in /v/ discussing both of these games, it went on longer than expected with both sides showing lots of support. Let's try to continue the discussion here: What series is better? but most importantly, why is it better?

Metal Gear Solid, IMO. I like the over-the-topness, and fun boss battles.

And of course Snake would kill Sam Fisher. He can dig bullets out of his fucking skull with a knife. Let's see Sam Fisher do that. :)