I went flying with the Aware 5 today. For anyone who hasn't seen an Aware before (is there anyone?), it's a very simple GPS with a digital CAA chart which has an underlying airspace database that's used to provide controlled airspace warnings. The '5' is a bigger unit than the original, but works in exactly the same way.
In most light conditions, the screen is easy to use, although there are times when the bright sunlight makes it difficult. The GPS finds itself quickly and the battery seems to be coping well (an hour-and-a-half so far). Airspace warnings come both on-screen and audibly - and even without the unit being somehow plugged into the intercom, the beeping is audible above the 182's Continental and through Sennheiser's ANR. The only complaint is that the supplied suction mount is about as cheap as they come, but there are plenty of other options available to the resourceful pilot.
For £249 it offers good value, and instant situational awareness.