A guy I used to work with took a 2 year oil field course at SAIT and has a really well paying job now.
Really wish i could remember what he took. The only thing is, you can get a good job, but i don't really know how far you can go on a diploma (compared to a degree for promotions and such).
May not help much, but there you have it.
Edit:
I had the choice to attend SAIT (2 year) or MRC (4 year degree) for my school, and although i can get a job right away with SAIT, if i want to move up, the degree will seriously help, plus get me a better job and go where i want to go. Thats why i chose the degree. 2 more years, but down the road, it will pay off... i hope.