I've only played a few Metroid games and although they were fun, they don't quite draw me in like Zelda games. Even today, A Link to the Past/Ocarina of Time are still 2 of my most favorite games.

Zelda, but it's a very tough one.

Zelda has to win because it's concentrated awesome but I absolutely love the Metroid series too (Prime and Super being the best)

Metroid, I liked Prime 1 and Super Metroid more than any Zelda game I've played so far.

Metroid. Scanning is awesome, on-board computer is better than a fairy guide, and integrating your gizmos into a single suit of power armour is better than Zelda's infinite sack of inventory management.

Well......

Top games in order for me:

Majora's Mask
Ocarina of Time
Wind Waker

Metroid Prime 2: Echoes
Metroid other M
Super Metroid

*It's tricky but in the hands of a top developer like RETRO I rather have.....Metroid.
*Depending on the new direction of Zelda my preference can change. Skyward is a good game of course but overall it felt like something was "missing." It was pretty much a hub world like Mass Effect.

*Metroid has been drawing my attention more lately so my answer is METROID. 

I've never played Metroid. From what I've seen though, I'd definitely say Zelda looks better and more original.

Same here sexy!

No doubt zelda

@spurgeuss. I think it is, Metroid is one of my most beloved franchises.