Yup my dad uses one of those it seems ok and if he can operate it I'm sure you'll be alright the new tomtom home thing makes updating it pretty easy too.
I've got one of the new tomtom one's and its pretty good! I use it every day for work and its saved me soooooo much time.
its not for me, i'm happy with an atlas and my my own sense of direction, not failed me yet. but cheers for the reviews