I use both here without problems and there are pros & cons to each.

If a snake regurgitates it's meal into the substrate, you are more likely to notice it quickly and remove it when it happens behind glass.

In a rack, that regurgitated meal could sit there a while before you notice.

I have witnessed a snake attempt to re-eat a barfed up pinkie all covered in substrate, it was stopped and I threw the pinkie away.

If the snake starts convulsing, what chance of intervention is there if it is hidden away in a rack?

Many of us prefer to see our snakes, glass front vivs are the best way to observe your snakes without handling them.