I don't like it, it requires more powerful CPU, larger memory, cannot resell when mining crashes.
Another important thing is ,small rig with 6 cards is more flexible, you can run windows in a rig and linux in other rig if needed. For example, if there is a miner only supports windows, but your 12 cards rigs are running linux, and windows only supports 8 cards, how to switch?
You can run 8 AMD and 4 nVidia together in Windows.