Not sure about the big black arrow (it has dozens of features I don't use), but the 500 is less user friendly than the 100. BUT...you'll forgive it that minor flaw when you see how fantasticly readable the backlit screen is. I'd like to have a panel mount 5" color GPS, but short of that, I'll stay with the 500. BTW, mine is yoke mounted on a compact mount I made...very easy to use, never in the way, and reasonably un-ugly <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />
