[G6Tanuki]

As regards RFI from an in-receiver digital frequency display, I never had any issues regarding this when I used an Ambit "DFM7" kit [which used the nice little LCD FC177, which conveniently allows you to add diodes in various places to select the necessary frequency-offset].

LCD counters need only a few Microamps of power - meaning they're not switching/multiplexing significant current and so are intrinsically a lot quieter than old-style LED counters using TTL dividers etc.

One thing to watch though - quite a few frequency-counters have a long 'settle-time' meaning their display tends to be slow to catch-up when you change frequency. This can be really annoying - even back in the 1960s they got-round this by driving the Nixie-tube frequency-displays on professional receivers not by counting the actual VFO frequency but by using binary data from the encoder-switches that also fed the loop divider-chain.