Thinking about downloading via the Garmin POI loader to my 2720, but I wondered which is recommended and whether they cover UK & Europe.
Any other tips or advice appreciated.
As John has pointed out, there are two types of 'speed camera databases' out there. The kind you want is what is referred to as a 'Custom POI' database. This type of database is used by the newer GPSRs such as the 2720 and 2820. You can see pictures of the type of warning you get from this on the first page of the discussion of the new 2820 GPSR - click here: Garmin announces the 2820 GPS for motorcycles. Your 2720 works exactly the same way, no differences at all.
There are 'overlay' files that have been created for older GPSRs that do not support CustomPOI files. These are something that very creative end users of the GPSR developed - Garmin themselves never foresaw the use of these types of files (though I suspect the software engineers admire the creativity and skill of the end users who create these files). You really don't want to have anything to do with overlay files, because they don't provide the visual and acoustical warnings that the Custom POI files do.