I have Doepfer cases and MDLR case. By far, love my 14u MDLR case. Here is why:
2 rows of 126HP for 1u tile modules: Intellijel 1u are super ace
4 rows of 126HP for larger modules that are HP pigs like Rossum and 4ms modules- I am looking at you wonderful HP piggies.
Two massive 85W power supplies- never had issue power modules even piggies like Rossum Trident and Mob of Emus. Funny the modular guy at Patchwerks I think mentioned someone had issues power Mob of Emus in a smaller case. Not me!
I bought smaller 6U case in the beginning and was a mistake! You will want the larger piggy do cool modules sooner or later and not many fit and leave room for the oh so critical support modules like matrix mixer, attenuator/attenuverters, VCAs, LFOs, sequential switch, etc.
I am now a fan of MDLR cases they fold easy and come in all sizes. Not cheap but hand made of nice wood and well engineered. They make a 9u and 12u case if you don't want to go supersize like I did. Plus knurlies fit easy. I had a hard time screwing in knurlies to Doepfer monster base case.