Several readers asked me about the Nikon GP-1 since it is still not available for sale online. Here is a review I came across - it seems that the GPS is working very well. Read the whole (short) review here:
"I have to admit, I’m impressed by the GP-1’s speed of acquisition as well as ability. I’m sitting at my desk in the corner of our office and while the other GPS units I have cannot find a signal, the GP-1 has blinking green light in 5secs, a solid green light within 15secs."