As a working musician in Australia, I travel a LOT outside mobile coverage. Navigator is o.k., as long as I'm in a network coverage area. Navdroyd is a bit toytown, but the price is right.
Just before last weekend's trip I installed the demo of Sygic Aura and it's blown me away. I've never had a "real" GPS unit and so can't compare but I really like Sygic and the info it offers.
Easy to read display(on HTC Desire HD) and all the info I want including speed limits and an above speed limit warning - when you've been driving for 2 hours it's easy for attention to wander and the speed to creep up so this is, while not vital, a big plus.
I'm still finding my way around it, and I can't figure out if there's a way to enter a street address directly rather than choose the town, then choose the street, etc.
I've ended up purchasing it, which to those who know what a tightarse I am is a big shock...