"Ive read about garmin 500 and clarity, but i fly a stampe and need one to strap on my knee, needs to be clear and bright and pick up a signal from my knee, any ideas out there? Thanks"
Mark,
I have no experience with biplane open cockpit.
I have a Garmin GPSMAP296,and a Garmin Area 500.
The 296 is slow to get satellites.
The G 500 fast - I suspect it has a Sirfstar III or equivalent chipset.
Fast also means sensitive and the Area500 will work reliably in poor situations that 296 more than struggles with - ie deep in a room with a large window, so I suspect it will work well in biplane but i can't be sure.
I prefer the G296 due ergonomics. ie buttons/rocker cf touch screen.
You could use the 296/495/496 with the external antenna connected - it works very well.
Hope this helps
John