+1 what Jim is saying…I started with just a Rackbrute 6U and that was all I was ever going to have…now it’s 2x Rackbrute 6U and a Rackbrute 3U :) I wanted some flexibility to use modular with some of the other stuff in my studio (Minibrute 2, Hydrasynth) and to be able to mix/match smaller setups to take with me when I wanted. If I were in your shoes though I would definitely get a Mantis as suggested… you can still just fill it with a few modules like a smaller setup would allow but you will have lots of room to grow if (well when) you decide to add more

JB