Ourt Garmin is the Etrex 20 , I did have the Etrex 10 for a short while but did miss the colour maps.
I got the maps from a site called http://talkytoaster.info/ukmaps.htm , very easy to download onto a memory card and load onto your Garmin
( not sure if the Etrex 10 had a memory card slot ).
The only difference between the 20 and the 30 is the 20 hasn’t got a barometric altimeter, wireless data sharing, and a 3-axis electronic compass.
Apart from the unwanted waypoints due to the joystick as mentioned by Tamerton Chocolates I do find it a easy piece of equipment to use .