I have a Nikon GP1 GPS now about 14 days and had a few times so rehearsed, I can not determine negative Neither consumption nor long waits. Maybe it also depends on which camera to the GP1 is connected, for me it is a D3. It's all as described by Nikon cold start 45 sec and then a maximum of 5 seconds and I find OK. Only the cost seems very high, so one star less. But if you have opted for Nikon it's pretty clear which one gets nothing more than cheap inexpensive. To me it is but the thing worth. I have about 30 years Nikon and never regretted. Conclusion: I would highly recommend the GP1.
