That's a decision you should make. Only you know what kind of duty cycle you should require, and what environmental issues might have to be considered.
Most warehouses I service run HP Laserjets, and they work quite well.
As for your font requirement, that is usually an add on component. I think you can get these with the Laserjet 4000 series, which is a series I commonly see in warehouse environments.
Matt J.
Please always take the time to backup any and all data before performing any actions suggested for ANY problem, regardless of how minor a change it might seem. Also test the backup to make sure it is intact.