£36 per year does seem rather good value for all the database updates - Does anyone know haw much Garmin charge for their updates?
$49 on line on their website (click 'aviation databases' at the bottom right.)
The Garmin database is Jeppesen, updated monthly, update as often as you feel necessary for a VFR piece of kit.
You get one free update code with any Garmin aviation unit - it's supposed to take care of the fact that the unit has probably been in the box for over 28 days when you buy it so you get a totally up-to-date unit, but you can keep the issue database for a year and then update.
The Bendix AV8OR is on the same system - you only get one update for your £36, not a year's worth.