I use a Garmin Aera 500.
It is a really superb piece of kit, needs an hour or two with the manual to learn your way around the finer functions, but once that's done really useful. It has saved me from severe embarrassement several times.
The 510 is a version with better resolution terrain mapping and in the USA (where I don't fly very often) things like weather downloads - I am sure it's better than the one I already like.
Downsides:-
- You're limited to an hour or two if you haven't arranged to plug it into an aircraft power supply.
- The map updates are expensive.
- A little difficult to use the touch screen in turbulence or whilst wearing gloves.
- The initial airspace warning settings aren't necessarily what you want, and working out how to change them can be a mild faff.
And it's still no substitute for maintaining a proper plog and nav regime.
G