I have a Jeppesen "aviator" bag. Pretty tough, comes with headset bag and one for a transciever (I keep an overnight kit in it but), and fits 2 Jepps + Ersa + approach folder + room for a little bit more in the main bit, plus maps and nav stuff in the zips. Haven't had any trouble with it at all, can highly recommend the quality. If you need more room the navigator or captain bags are probably just as good, I personally found them too bulky to consider keeping one in the plane with me. To each their own!
