I would've voted tupperware - but don't have a rack system (yet heheh). We've got a mix of both glass and plastic enclosures - and while I really LOVE the ease of maintenance possible with plastic the lack of real transparency leaves a lot to be desired. Recently had to take our AfRock Neph out of a big tupperware and put her in a huge 55 gallon only because the lack of transparency heightened her isolation - and when you opened it she'd give a loud ole hiss as contact (visual if nothing else) with people was lacking. That was a lot of lid to slather with con-tac paper heh. The ease of maintenance gets to be a really huge factor when you move up beyond 10 gal thanks - they become increasingly heavy - the 55 gal i had to prep for Neph weighs nothing less than 80lbs. If you have a single or couple of herps glass may be quite doable with a smidge more diligence - when you have an increased number being able to maintain everything at a level of good husbandry may demand something more manageable.

Now if they could make truly transparent plastics less brittle - or make these awesome Sterelites more transparent . . . . . .