SM sounds really strict. I don't know about the others though.

there are a lot of labels you could choose to train under, and I know that SM is the most available, but it TOTALLY depends on what you want to do first and foremost.
for example, if you want a seriously music focused career (including composing, or producing,) SM is NOT a good option for you.
however, SM has some of the best dancers out there. if you're in it more-so for dancing, this may be a better company for you-- but there are a lot of other labels who have great dancers, as well.
SM also trains their artists in a variety of things, which is great for the idol image, but chances are there will only be one or two things you'll really excel at.
I will admit that I do have a bias against SM, even though I love so many artists from the label.
all these entertainment companies have different ways of going about things, and training their artists, and you should definitely research them all before you consider auditioning for one!

they pay for EVERYTHING. Your education, the place you stay, food etc; you also get some allowance.
If you want to go to a college there, they will pay for you. You train for basically, everything! Like Dancing, Singing, Acting, Modelling and you learn Korean as well.

There are two buildings, one for males and one for females. One dorm room has about 8-10 people and in each room there are 3 people. You wake up at 6, go to school at 7, dismissed at 3:30, Train from 4 to 9, and get to bed at 10 so you could have an 8 hour sleep.

being a trainee anywhere would be hard,it's best if you ask people who are non-biased ;X people who dislike a company would obviously tell you that it's horrible and that you shouldn't go there.

If u really wants to be an artist, SM entertainmentcis totally not a good choice. SM totally doesnt take good care of their trainees. My sister was once a trainee in sm entertainment but she could not take the presure LSM is giving to them, trainees and she is now a part of the cube trainee.
If yoy really wants to be a trainee, JYP family would be the best choice ( well, i think ). Although YG entertainment is so called the best entertainment, but their rules there us damn stric and its not easy to be a trainee there.
JYP has a very good relationship with JYP family. Like 2PM said before that when they does not like the song JYP created for them, The will totally denie it cause JYP would not really mind.
Well, i had been to JYP entertainment's building since my eldest sister is a cheography there. Their bonds are the best!

if i am u, these are the entertainment i would choose to try out.

-JYP entertainment.
-Starship entertainment
-YG entertainment ( but will be hard )
-Loen entertainment
-Cube entertainment
-T.S entertainment
-Star Empire
Entertainment

Well, even if u debuted in other agency, u will still be able to see ur idols...
wish u luck :)

It's highly strict. The work ethic in Korea is much different than the "American"/Western style.
You have to be able to maintain yourself as a trainee, as you are responsible for any fees. Not only that, but you have to be physically, mentally, and emotionally prepared for the years to come before your debut.

SM treat their stars like slaves.
They get less paid than the people cleaning toilets at your school.
They get 1-2 days of vacation per year.
They force them to diet and many times do plastic surgery.

Yeah, I know that SM make great videos, but don't get fooled. Kyuhyun, the youngest of Super Junior, had to sleep on the floor for several months. Many of their artists faint due to malnutrition since tey don't get enough food.

If you want to be a Korean popstar, sure. most companies are fine. SM is not.
That was my advice. But you can, of course, do whatever you want to.

It would probably be strict. I haven't a clue though. XD
Just go for it. :3