They are still the norm in GA piston twins. I've flown one piston twin that had a RMI. Fixed card in everything else, and true to GA form (and ADF/NDB form), varying degrees of randomness in every relative bearing I've seen. Although illegal as hell, it's probably safer shooting a NPA off an iPhone than an ADF/NDB alone these days.
Conversely, never flown a turboprop without an RMI.