Updating GPS data?
 

There has recently been some discussion on this forum about GPS, and its use for navigation here in the UK. The consensus appeared to be that if you've got it, use it but don't rely on it as a primary navigation tool.

I agree with that consensus view. However, in my aircraft there is installed a Garmin GNC250XL which uses a Jeppesen NavData card. This is out of date (by some 3 years).

If I only use GPS as secondary back-up to the trusty Mk 1a eyeball and an up-to-date map, are there any pressing reasons to go to the expense (~£350) of annual udates to the NavData card?

I think you answered your own question! If you use it as backup, and have a current chart in your hands, there's no need.

My little Garmin has a database that was wrong when it was "current".

Garmin/Jeppesen haven't fixed the errors in how they display European airspace yet, so there isn't a lot of point in spending good money to update it to something different, but still wrong.

You may find your 250XL has the same problem. Check - does it show Class A airspace round Heathrow? Does it show the Airways as Class A? Does it show ATZs at European sizes (2 and 2.5nm) or US sizes?