I've only had dealings with Mutable Instruments and Befaco - both were great...
Mutable regarding a switch that failed and needed a return for repair
Befaco with questions about DIY modules
"some of the best base-level info to remember can be found in Jim's sigfile" @Lugia
Utility modules are the dull polish that makes the shiny modules actually shine!!!
sound sources < sound modifiers < modulation sources < utilities