i am also interested in this, is there any software that works with 5hz?
as for the software only working with 1hz, you will still see an improvement, i would think a very noticable improvement. most of that improvement would be noticed in speed accuracy and when stationary. i would like to throw one of the gps receivers from work into the car and give that a go, 25hz with beaconor other external corections

but for the $2000 i dont think its worth it

and a car doesnt need 2cm accuracy..
does anyone know about mapmonkey or freedrive, or more in particular destinator, if it works with 5hz or just 1?
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