I really like both of them (or it seems like) which one should I buy?

Also I can get that Lux Skin that is on sale right now with Lux too!
So what should I get?

Give me pros and cons of both!
I like laning, I am level 12.

Never played Garen, but I know I hate playing against him.

Lux on the other hand, is awesome and just got a slight buff in the new patch. I play her regularly as an AP mid with pretty good success. Stun, slow, AOE, and a huge ult make her really fun to play and get lots of kills with.

I don't know much about Lux, however Garen was the first champion I bought and I enjoy playing him regularly. Certainly a major pro about Garen is that he can be pretty flexible. It bothers me that people think of Garen as a main tank, given his incredible lack of CC, but he can be built to be a pretty impressive offtank, or you can build him to dish out quite a lot of damage.

Garen pros:
Simple to play
No mana

Garen cons:
Drops off late game
No CC
Easily countered

Lux pros:
Good burst
Versatile
Hard CC

Lux cons:
Squishy
Skill shot reliant

If anybody disagrees, tell me why.

I might also add, Garen has a very strong ultimate. It's on a pretty long cooldown, but I don't think there's a better ability in the game for finishing tanks (I may be wrong), and it's of course useful for finishing of every character, but certainly tanks.

I just bought Garen. Already destroying bots
Thanks for the suggestions
/reqclose

LUX is worth it for her ULT alone... It's so satisfying to get that kill as the enemy retreats....

However, always make sure you have enough juice to use that ULT after an exchange with an enemy player because as awesome as it feels to burn them down during a retreat - it sucks much more to not even take the shot due to low mana.......

You won't be disappointed.....

Lux seems pretty cool, however I have personal experience with Garen. Garen isn't as strong against other tanky/dps melee as you would hope. Against Darius he can't trade hits, along with many other high output champions. However, laning with another strong melee can yield a quick gank before minions roll out at the start of the game and as such he can farm in the time that it takes for the ganked opponent to return to lane in turn creating a level deficit between himself and his laning partner and his laning opponents.