I used my TomTom GPS and my HTC Evo GPS on Hawaii. Both worked great. The Evo GPS was amazing though. It had amazing detail, speed, and reception. I was able to get GPS lock 2 levels deep in a concrete parking garage.

I ended up relegating the TomTom GPS to back up duty, while the Evo was my main GPS.

It was fantastic to have such useful tools while traveling in Hawaii!!!

-- - red light cameras do not work