Hi there,
I can't say anything about CoPilot, but after reading the comments section in the android market, I ended up getting
Sygic's solution direct from their website.
I was on holidays in the States for 3 weeks there and rented a car for the whole time, so that's why i got it. In short, it's REALLY good.
There's a small learning curve in how you search for POI's (not as simple as Google Maps' "type-and-find", but that's the same with all standalone gps), but literally every address and every possible POI i was looking for while over there was in it. There's also "history" and "near me now" functionality to speed things up. Seriously, couldn't have got around without it - used it to find Diners in the morning, beaches and malls during the day, and my way home at night! It also has phone numbers for nearly every POI.
It's also pretty quick at starting up, extremely quick at getting a gps signal, and never failed route-wise. Phone calls, texts, web browsing etc also keeps the app running in the background, so no need to worry about re-doing everything if someone calls while you're driving.
I might have only used it for 3 weeks, but it was the by far the best money i spent on anything over there!
edit - also, i'm struggling for phone memory on my milestone at the moment, but the app only takes up about 6.5mb which was obviously a huge plus for me!