iPhone 3g GPS inacvtive

When I bought the iPhone I noticed that there was an incredible lag when using Location Services. Today I asked the Maps application to find my current location. 20 minutes later it was still thinking.

I called Apple and, after a bit of searching, the tech gave me this solution:

Turn iPhone off and back on.
Disable 3G.
Disable WiFi.
Use Maps to find current location (worked!)
Re-enable 3G and wireless.

I power cycled again and my GPS was still working.