As a teacher - DEFINITELY doc martens. Worn the same pair almost every day for over a year and they are still going strong and my feet never hurt in them
I used to work for Reiker a few years ago and I have to say, they are the most comfortable shoes and boots I have ever worn, I do genuinely recommend them.
The Vlarks Unloop are the most vomfortable shoes ever, just not pretty. Having had PF before, I wear these mainly for work and then Fit flops (blue light discount) out of work