showroom performance ?
Wonderfull things these Garmins but when flying IFR I find that the Garmin is a bit fiddley to use and it requries a lot of messing about to get the data that I require quickly..........its all in the box just hard to get at !.
The big map is of very little use when flying IFR and all the ground features just get in the way.
Changing frequencys during turbulence is a pain due to the way the cursor has to be used.
My last MEP/IR renewal was done on a garnin equiped aircraft and I found it OK but just OK.
The King KLN units are much better suited to IFR the logic is very close to the Flight managment systems on the bigger jets and having not much map should not be a problem after all most of the garmin map is just a VFR chart "security blanket".
My favoured option for the IFR fit for Hairyplanes Robin taking into account the robins modest pannel space would be:- King KLN 89B or 94 GPS , 2 KX165A nav/com's KN62 DME (yes the 100w unit!) KR87 ADF (Narco ADF ? dont even go there !!) and a KT76? mode S transponder for the the audio something from PS engineering who are the masters of audio (apart from one unit that has a few problems).
NO MAP !!!! the cry I hear from the cheap seats!...........At the moment Sandel are about to produce a daylight any angle readable Glass HSI/ ND with a 2000 hour lamp to drive it , the shipping date is april 2005.
This unit will do most of what you want in terms of diplay along with the King GPS and mode S transponder and an fuel/ADC from Shadin will do 98% of what an airliner FMC will do at a fraction of the cost.
And once the whole lot is in the aircraft dont forget to get a cooling fan .......worth its weight in gold.