I believe that the Garmin GPS 16A updates 5 times/sec. It is very expensive though, upper $200's. I am new to the GPS arena and doing my research now, but I expect that update time is only usefull if the software can be configured with a similar setting. I am looking at the GPS 16 (WASS, updates 1/sec) because everything I had read from users seems to indicate that it locks faster, AND can be mounted inside a trunk and still get a signal, unlike others. (My other choice would be the DeLorme Earthmate). Anyway, look for information on the Garmin GPS 16A, check their website they had info about it.