MCU has scribble strips on the unit plus time code section. BCF has a virtual scribble strip, no time code.
MCU has indivdual buttons for Mute, Solo, Record, Select the MCU needs a modifier for solo IIRC?
Other functions on the BCF require a modifier and there is only one as opposed to 3 on the MCU and therefore access to fewer (if somewhat obscure) functions
MCU has a jog wheel BCF doesn't.
BCF can be used as a controller for ACT etc, MCU can't
MCU has a bigger footprint, you can see the difference in my photos above. (I now use the BCF as an ACT controller.
As an ex-BCF now MCU user I feel I can answer these questions subjectively......
Is the MCU better? Yes.
Is it £1000 better? Not even close.
The BCF is IMHO one of the best value bits of kit available. If the MCU is at a bargain price it's a far harder choice. At list the BCF is a winning no-brainer. IMHO of course.
HTH