Perfectly okay for those who are not picky. The speed of the mapping depends on how detailed you want it and how many maps that are "activated" However, it is somewhat dull matter. Have used it on various tours and trips and it has "done its job".
I will supplement with a GPS that draws the maps slightly faster. Otherwise this "ok". But NOT for the discerning.
GPS is quick to draw maps, lies well in the hand and has a great battery life. Unfortunately preferred software by many annoying bugs that unfortunately drag down the score significantly. eTrex 20 has the same software as the problems are also likely to affect it.