OK so, I've been playing LoL since 3 years ago (as I said in the title) and all I can recommend you is not to download this game. It has the worst community that could have ever existed in the gaming world, because it's filled with 10 years old kids who can't accept losing and have to blame others, douchebags elitists that think they are the big cheese because they have a nice skin and some kills, so they start shittalking everyone that makes a mistake (including enemies); there are also some idiots who just play blind pick and dodge/troll/feed if they didn't say their lane fast enough. Everyone is toxic in this game, unless you simply don't give a shit about what other people say and just wanna have fun (like I usually do) so unless you're a cynical piece of shit (like me) or you have 4 friends to play with everytime, then you shall welcome this game. But there are some other cons about this game, and one of them is Riot Games itself. I've played in NA, and LATAM (both South and North) and the difference is majestic. I would accept a difference between NA and both LATAM servers, but the thing is that the South one and the North one ARE ALSO DIFFERENT, different in a way that involves south part getting better events, more attention from Rioters and some better offers, but the community doesn't really change its shit status :P. Also, Riot has made the champions and IP system just so it is really annoying to make good IP (unless you play and win a lot), so you just buy RP. And now you don't get 400 RP when you hit lvl. 10, but you just get another hextech chest that has just Ashe fragment, Garen fragment and a bunch of blue elixir (you probably won't get this if you don't know anything about the game, but it's kind of a shitty change), so you can buy a random fragment and make a RANDOM champion or simply get the permanent champions/disenchant them, but the thing is that with the RP you could buy any 3150/- champ, so you don't leave it to the odds (this is not SOOO bad but it's worth pointing out). And one con more, the champion balance system. Dear God. The balance system is just, woot? Riot buffs champs that are really strong, and nerfs champs that are simply falling. They don't always do this, but it is pretty annoying when they actually do. I forgot to mention the Dynamic Queue, which is the bane for all good ol' SoloQ players because now they find premades of 5 people that communicate 3 times better than a team filled with flamers and idiots. Also, dynamic queue takes PRETTY LONG to find a match, which usually get cancelled because of a guy that didn't accept the match, because someone dodged or just because 1 or 2 AFKs were in a team and they did /remake, but they're going to remove Dynamic Queue so stay calm ;).
Enough bad things, let's get the good things. The design of the champions is actually good (but usually their abilities are OP on release) and it's a fun game if you know how to simply keep the shitty community outta your mind. There are a lot of champions that require a high skill cap and can be a self challenge, if you like them, or you can play just casually with an easy, fun champ. There are also hard and fun champs like Shaco. Riot is active with taking out new champs, skins and that stuff, and (sometimes) pay attention to the community. Also there are always leaks (be them from the community or from Riot) of the new champions, or teasers, so stay in touch with the forums or something like that, because it's kinda interesting. Also, there's the game rotation which enables a gamemode for every weekend (from friday at 1 PM to the beggining of tuesday) and the gamemodes they get are really fun (like AR-URF or hexakill).
1 suggestion I have to make is, wait like 1 year, and then get on Heroes of the Storm, or just join it now. I actually prefer it just because the teamwork must be strong and the community is less toxic. Also it's from blizzard and all the heroes are from their other games, and there's much more variety on maps. And it's pretty much balanced, except for some heroes that are kind of stronger/more picked.
This will be all in my review, I hope it helped, and thanks for reading. Don't mind if I ranted a bit on the cons, I'm kind of tired of playing it and I'm starting to hate it :P, there are some cons I didn't actually point out but it's ok, I think those are enough. I'm out