I just started playing MSX version of Metal Gear 2
And my god, this game is incredible. Such an exceptional game from an 8-bit system. I'd recommend it to anyone. This game actually has a storyline like no other game of its era, and it's a drastic improvement over Metal Gear 1. From the gameplay standpoint, it feels like MGS in 2D.
You can grab the translation patch pretty easily off of Google.