All that said, if you find a school that comes highly recommended, either from a friend or someone you trust, by all means don't hesitate to sign your ass up for a year if you think the benefits are there. Oftentimes, the end of the year bonuses are bigger, or you might have a pay raise (typically 500 RMB after the second semester or term). Just be aware of the fact that the teachers in China who dislike their school are far more numerous than those who like their school. That's my experience, and the experience of most teachers I know anyhow... Do you best to do your research and you should have no problem finding a decent situation for yourself.
Now if, after all that, you still sign for a year and for some reason or another they manage to piss you off with silly demands, a broken toilet, or constant power outages (just some examples) - DO NOT, I repeat, DO NOT pull an Incredible Hulk and explode in a fit of green rage. DO NOT mention how you may have passed the previous evening with you boss's mother. Just don't! Here's why:
In China, you must change your mindset in order to prosper. You must be bamboo, my friend. Yes, young Skywalker, China is full of the dark forces of corruption and bad management and lots of other intolerable shit. If you cannot bend and flex under such pressure, you got no other option but to snap. Know your rights and stand tall and firm, but assert them in a voice quiet enough that will not rock the proverbial boat. At the same time, be strong enough to let people know you aren't to be cheated or taken advantage of. Keep this image of a tall and strong, yet almost silent bamboo tree swaying peacefully in the breeze, and you'll do just fine in China.
Moving on... The 6-month contract has it's advantages for sure. If you find that China is not for you, you can get out after a relatively short time period, rather than being "morally" obligated to stick around for a year. Some teachers do a "runner" mid-contract, and I'm not gonna comment too much on that. Every situation is different. But I will say this: A lot of those teachers that run off mid-contract, do so as a result of having not thouroughly researched the school. As I said before, do your homework!
Now signing a six month contract may not have as many perks as a longer one-year contract, so that's also something you need to consider. Also keep in mind that some schools are quite willing to allow you to re-sign after those first six months. If this is the case with you, try to make sure that you are receiving the same benefits that you'd have gotten if you'd originally signed for a year, rather than having two 6-month contracts srtung together, with less bling earmarked for you.
There are also other ways to go about teaching English in China. Many schools have summer programs that just might be a good fit for anyone who is especially worried or anxious about what awaits them in the Middle Kingdom. A summer fling with this Asian hottie (ok, maybe "hottie" is a debatable choice of words) might be what the ESL doctor ordered. I once was employed in what's called an "Intensive" summer program, for 6 weeks during the months of July and August. This job required about 30 hours of teaching per week, which wasn't really all that intense, though I was glad to see the end when it came. This kind of program is definitely good for breaking in young ESL virgins, and showing them the ropes so to speak. It's a testing period of sorts, not only for the teacher but also for the school. If the date goes well, and if you manage to "get some," who knows, maybe both parties will continue the fling into the fall?
Another option that many people don't consider is enrolling in at a university here in China for mandarin/chinese language study, often teaching English elsewhere (usually at a private school) to pay your way. The money I made during my six week summer intensive period paid a full year of tuition for my Chinese language study! For anyone who wants to make the most out of their time in China, it's definitely worth the effort. You can speak to about 10 times as many people (even if it is in broken Chinese) as you could before. Isn't that worth it?
My Chinese study is only 20 hours of classes a week, which allows for lots of "other stuff." I'm not entirely sure of the legalities of obtaining work on a student visa, but like most rules in China, if you're sneaky enough...
Actually, some of my Chinese teachers have asked me if I'd do some private tutoring for them. Now, although I didn't take those jobs, my point is that even your teachers will often give you the green light on this issue.
I do know, however, that is is legal to study on a work visa (as opposed to working on a study visa). I have many classmates who do it both ways, to be honest. But studying while on a work visa, if you wanna pull it off properly, requires getting an English Teaching job with minimum workload. An ideal situation would be a fifteen hour contract at a private school, with most or all of those hours on the weekend, allowing you to focus on your study during the weekdays. Of course, you may even have an apartment thrown in as well, in the case that you don't want to pay for on-campus housing. Secure the job first, then enroll in classes. It's easier to enroll in Chinese school in mid-September, than it is to find a decent job at that same time.
Anyway, that's my two cents. Keep in mind that the situation in China is always in flux, and rules and regulations change like the wind. I'm writing this to share what I've seen and experience, not to tell you what to do, but so that you can be prepared to make well informed decisions. Consider me your best friend who gives you the run down on the chick you're about to be set up with. She's a shapely wench, and while her armpits stink from time to time (see Shenyang), you may be more interested in the hotter bits to the South. It's up to you. Plan your moves carefully and you just might get lucky by the end of the night!