EASA STCs are finally appearing for the EFD1000. Lees Avionics at Wycombe Air Park have just been awarded approval for the Piper PA28 series and say they'll have PA32 and PA34 STCs in the next few weeks.
which ensures that only that avionics shop an do the work (or alternatively they sell the rights to the "design" to other avionics shops who then have to charge their customer) which is hardly conducive to providing value for money to end users.
This is a crappy situation. One could blame EASA for it, for being stupid and not simply recognising FAA STCs, but in more general terms one could also blame the US manufacturers for not bothering to certify their stuff for the European market.