I've seen many phantoms with stickers or paint on the top shell of the phantom. Won't this affect the GPS signal? Can somebody give us their experience?
How many sats will you lose (Obviously it will depend on the material and thickness).

I use the phantom for filming and don't care much about the looks, who cares that birds see a colourfull phantom - just beeing curious.

i thought about this too.  am i mistaken or doesnt the gps signal only get blocked by thicker solid surfaces (like walls, trees, thick moisture in clouds, etc).  seems like from a relative standpoint, a film/sticker on the outside would be 1/1000th more material than the shell itself so if the sticker would block anything you'd think the shell would have more of an effect already on its own.  of course i dont know much about the engineering so just speculating.

If you place your hand over the GPS unit you will loose all satalites - so where to draw the line?

your hand is like a billion times thicker than a sticker so while i get your draw the line comment, i certainly wouldnt draw the line anywhere near the sticker side of that equation.  however, like i said, im no engineer.  i do plan to put those decal stickers on mine that you reference though.

I just painted mine and I will report back once I get it back up in the air to check sats.

My Hanger
Phantom 2 w/H3-3D gimbal & GoPro Hero3+, 600mw 5.8vtx w/VAS BB Ultra, Large Skids
Phantom 2 w/600tvl, 600mw 5.8vtx w/VAS BB Ultra, V2 ESC's, MultiStar 2212 Motors, Custom Wood Skids
Lumenier QAV250 Carbon on 4S, Cobra 2204/1960 Motors, KISS 18a ESC's, Aero Guard, CF Camera Mount, CC3D, FrSky D4R-II, Mobius
Hubsan X4 Stock mini racer, Hubsan X4107D Non FPV(now) racer project, Taranis X9D w/external Antenna & 2200mah lipo, Dominator V2's w/goggle mod

I have a bright red vinyl sticker from  Ebay and I have no loss of satellites.  I always have 9-12. To me, the bright red is valuable should I lose it in an unexpected fashion.  

-TSP181

I painted my Phantom but I made sure the paint was non-metallic. On of the stickers I was going to put on top was an American flag but it had a metallic backing so it's on the arm. There is no noticable decrease in satellite availibity.