As many posts suggest it really does depend on where your students are going with their flying, what their background is, what demographic you are targetting, where you are operating from, etc to mention but a few.
I would vote for a sturdy low wing trainer everyday of the week and would be happy to never see a C.150 or C.152 anywhere but a museum. They are just to underpowered
If money is an issue then the PA28 family and the Robin family are all wonderful, forgiving trainers.
I have nothing against high wings but for our general weather and flying conditions unless your students intend to purely fly GA local flying I would suggest the way forward to be low wing as a trainer and if they wish to move on to C172 et al after they gain a licence then so be it.
Happy hunting
