I am using a Legacy R4LC with the rare Legacy DCDE available for a few months, now NLA. The only reason I went with Legacy here was to be able to drive the Vision 700E RS6 board. This before you could buy RCMCs outright. So far no luck having tried all versions of R4LCs and building an interface to invert serial data to the IR transmitter. Ironic if all I needed to do is put in a TMCC feature code.
Pete