just spotted this thread (! )
herewith my contribution
I think real glass has superior and longer lived optical qualities than acrylic or plexiglass equivalents
I use toughened glass for my big wall cases--bit individual small cases are plain glass--I simply exercise a lot of care when transporting models
I have never had one break--and I have about 80 of these cases (! )
enclosed a few images of the cases that I have made for all my models
Note the glass is inserted into a routered wood " extrusion " with channels for the glass sheets
and the glass case fits over the raised model ' bed'
that way they are almost hermetically sealed and no dust. spiders or similar can enter
it also prevent the lids lids accidentally slipping off and damaging the model
Hope it is instructive
regards
JB