Yeah, you don't wanna get me involved in a GPS max speed pissing contest:
It's obviously incorrect, but it
is the readout on my device. Apparently it hadn't been powered up for several weeks when it was shipped to me after an eBay purchase, so the combination of time and distance from its previous fix had it fixing erroneously for a few minutes on power-up. It's fix would correct every few seconds, and the position change between fixes resulted in it having to have gone this fast to get there.
So I've never reset the max speed. I like it!