After over 6 months of editing without a GPS in my home city (and editing a good portion of Metro Manila during that time), I finally tested out the GT-31 GPS device, and the tracks were accurate. It was fun taking the tracks but I had a lot of difficulty in setting up the device a few days ago (even a few hours ago, I don't know how to operate this. Tomorrow morning, I'll go for a jog along Sampaloc Lake, which is cose to my place. You can find the trace made by the GPS here.