Having studied a lot of complaints about not enough detail, and checked out an example on Mapsource site, I bought this knowing what to expect.
It is not a replacement for a detailed map, but does give a lot more information than offroad on my satnav, (mostly blank).
I use it for geocaching on my Garmin 250w and so get a colour picture of water (lakes and streams), contour lines and some paths. Without it had just a blue line from my start point to target, and a second from my current position to target - rather boring.
Don't buy it if you want to find paths, but it does give some help towards the best way to go. Would have liked it to have shown type of terrain, but unfortunately not.
I keep the card in my satnav and switch from one map to the other. Only problem is to remember to switch between motorist and pedestrian and also to off road and possibly amount of map detail.