I used the Frequentis Voice Switch system when I worked at Liverpool. Worked well, reliable, versatile. A million times more advanced than the old Stratus comms panel (static shocks, buzzing and humming plus a daily failure).
They're fitting a Frequentis comms system in the tower here at CYQT later in the year to replace our 1982 piece of junk.
As for EFPB's, the Nav Canada system has been in the tower here since December 2005 (I arrived in Feb 2006) and everybody here swears by it (and at it from time to time
). In all honesty I couldn't conceive of ever using paper strips again. This is an airport where you can be sitting here scratching your arse with your feet on the desk reading Maxim then 15 mins later have 5 in the cct, IFR's from all directions, Water Bombers calling up for priority departures off the cross runway etc and all the flight data is managed by poking the touch screen with a few keyboard inputs. It's quicker and easier to manage and there's no straining to read your fellow ATCO's childlike handwriting during the hand-off!!
It's only failed once in the last year and we had to revert to paper strips for a few hours. However having subconciously dismissed the idea of ever using paper strips again nobody could remember the standard strip marking! We just muddled through and said a quiet prayer of thanks when it came back on.