A3 creates logistical problems and has very few advantages as the tutor would be viewing the images on their desk not on a wall in a gallery.

I have all my prints made by a lab, always did in the past, probably always will in the future. I use inkjet printers at colleges when teaching and they seem to take a lot of care, management and expense - which I prefer a lab to take care of for me.

It's to an extent anecdotal but with the SPI and Critical Eye I get to see a huge range of prints from many people and 99% of the time if the prints are poor quality they are home produced and the exceptional ones are usually lab produced. That's not to say that excellent prints can't be made at home but it's my experience it's rarely achieved and if it is it's the result of a lot of effort and understanding on the user's behalf.

I have seen amazingly good prints from inkjets but I also know the people who produced them have become expert in the subject - it's certainly not the 'simple as A.B.C' process that the marketeer's would have us believe!