My GPS SUCKED(!) until I flashed Phoenix ROM (4.1) with JK4 modem, and using SGStools to tweak GPS in LBStest tools. Its still not perfect but GPS locks on quicker, with accuracy down to 10 meters (sometimes even closer). Everthing else on my 1008 build runs like a rocket thanks to the dev (Adam) and crew. Suggest you try it if you're familiar with rooting/flashing custom ROMS.
