Anyone compare the three side by side? Which has the best "protection" for a sleeve? I know its not going to be too cushy, however, I'm looking for to place my Air in my backpack. Its currently in a mail envelope with lined bubbles. I just saw the belkin sleeve in person at Frys and its was okay, but I've heard great things about the incase neoprene sleeve for the air. Belkin is cheaper and on ebay its 16.00 but looking for opinions from those who have held both at the same time. Thank you in advance. Edit: I also looked an noticed the slim sleeve by incase. The incase neopreen states it has 3mm of protection, but not on the slim sleeve? Guessing its slimmer?