GPS suggestions?

coding1227:
I have used this specific model 6M:

http://www.ebay.com/itm/RYG25AI-u-blox-NEO-6M-5Hz-high-performance-GPS-antenna-module-battery-EEPROM-/181326135522

and

http://www.ebay.com/itm/1pcs-Ublox-NEO6MV2-GPS-Module-Aircraft-Flight-Controller-Arduino-/370851655655

Both work identically with the exception that one has the detachable antenna. Of course, the detachable antenna can be replaced with an active antenna design, if desired. But today's passive patch antennas seem to offer very good performance and also compact space - IMO.

Ray