I became increasingly frustrated with Garmin Express, which never worked properly with my nüvi 660, WinXP and 'down-the-phone' Internet, so now I use Garmin MapUpdater to download the full map set onto my laptop and the UK/Ireland set onto the GPS. Once that's complete, I use Garmin MapInstall to create a customised map set which fills the 2Gb memory - the full European mapset needs around 4Gb if not more.
Customised mapset building is a total pain though! Mainly due to the rather poor HMI Garmin use.....
A top tip - the UK/Ireland mapset also includes the following French maps:
Amiens
Bethune
Blain
Brest
Bruz
Caen
Dunkerque
Fougeres
Le Havre
Lille
Lorient
Nantes
Quimper
Rouen
Saint- Malo
Vannes
Vertou
It was like pulling teeth trying to get that information out of Garmin! I did once try downloading to an 8Gb SD card on Garmin's advice, but that crashed my GPS software, requiring a total reset. Which lost all my 'favourite' destinations.
Because Lifetime Update cannot be transferred to a new unit, even for a fee, Garmin are losing out because many of us will keep going with 8 year old GPS units rather than losing something for which we've already paid.