They fit a full run and you can buy extension stands to fit any variants. Drew also does customs sometimes, so might be worth messaging him to see what's currently available and if he can do something different. All the info should be on the website.
The best thing is the magnetised front- so easy to get the figures in and out. Some people even recess the cases so they are flush with the wall. They look amazing, but way beyond my meagre DIY skills!
Love those wall mounted displays.
I went for display units from Argos, great for loose and carded. Couple of DVD stands either side for mini rigs.
They do need dusting though so having them behind glass/perspex might be a good idea