In reply to gcandlin:
Jon Stewart's comment was fairly accurate. For me, the stress doesn't come from inside the classroom, and I consistently enjoy teaching itself. I have the benefit of a school with 'nice' kids and therefore that should be taken into account. This will depend on the school, but also whether you like teenagers. If you don't find them funny then this probably not the job for you - humour is essential, and finding it in most situations is a strength.
The interminable bullshit sprayed on staff by government, and then swallowed and regurgitated by management, is a serious headache, and as a new teacher, increasingly hard to work around. If you come into the profession with a clear aim (ie. English - teach kids to speak, read and write English to the best of your ability) then through a sense creative subversiveness it is possible to keep the job a satisfying and enjoyable one, but without that you are at the mercy of a management who are governed by OFSTED criteria and league tables, which gives the kind of target driven mentality and lack of foresight that has been working such wonders in the NHS. Unfortunately, with targets as the teacher's focus, it is easy to lose the human side of teaching.
An additional negative point would be the current government's focus on removing the teachings' pay and cxonditions structure. Holidays and pay are currently competitive, but they are quite possibly no longer guaranteed.
However, if you enjoy the classroom, can cut through the shite, manage the pointless paperwork, keep mid-management Himmlers sweet and manage the marking work load then it can't be worse than anything else, can it? I think finding the right school can make all the difference.
NB:
1) Don't know if Business Studies is an in demand subject so you could be looking at £9000 for your PGCE. Business Studies teachers can often be sidelined into IT which in some schools can be a nightmare with poor resources and a range of mind-numbingly dull quaslifications.
2) Holidays are good, but friends who are self-employed have more flexibility, and the option to travel in off-peak times is helpful. However, obvious downsides to being self-employed (not to be discussed here).
3) Did teacher training as a single-ish guy and although now married, do not have children. To manage that would be a serious undertaking.