We got Airspeed to fit a Funkwerk ATR833 (which we supplied from elsewhere) with separate SPA400 Intercom, and removing lots of redundant equipment for our PtoF SA Bulldog. The Batt light keeps coming appearing on the ATR833 but we can't blame Airspeed for that (and we ignore it without problems).
They did a neat job (reduced basic aircraft weight by 16.5Kg) and blanked off the spaces left by the old equipment well.
No complaints (and we struggled to find anyone else to do the work).