TRIMBLE
The upgrade mod can be done by AvionicAir at Southend and is quite reasonably priced.
If you have to use an out of date card it is legal if you verify LAT/LONGS of EVERY waypoint from an up to date chart!
I too quite like the Trimbles, but our units are 11 years old and they suffer from sticking buttons especially the enter button. Many trips to the workshop for new parts has only partially solved the problem, any one else experienced this?
Also does any one know how to speed the thing up. If there is a big flight plan in the system a "Go Direct" command from ATC takes a very long time, long enough for ATC to query you unless an intial HDG select is used.