The awesome uBlox 5 GPS modules are now available in the DIY Drones store!
From the product description:
The powerful GPS is based on Ublox 5 chipset and the Saratel helical antenna to maintain sat lock from any angle. Includes uBlox adapter and comes pre-programmed for ArduPilot.
* u-Blox 5H chipset
* Sarantel omni-directional Geo-helix S-type active antenna
* Real 4Hz Refresh rate
* Fifty channels
* Supports UBX, NMEA and USB&NMEA
* High immunity to RF interference
* Firmware upgradable
* Includes 12" cable with EM406 connectors on both ends.
The cost is $109.90, which is a bit cheaper than buying the module (if Sparkfun ever gets it back in stock) and the necessary adapter and cable separately, and these these come pre-programmed for ArduPilot, saving you a huge hassle involving making a custom connector for you FTDI cable and messing about with uBlox settings in their utility. It's designed to plug straight into the ArduPilot's GPS connecter--plug and play!
When you switch to this GPS, remember to change the configuration file so ArduPilot knows!
#define GPS_PROTOCOL 2 // 0 = NMEA, 1=SIRF, 2=uBlox