The sams club version of q-see (dahua) is actually 8 ch. 4 cam system same as the swann. The difference I see is that the swann has 1080p cams while the q-see is 720p cams. Also swann already has a built-in 8ch. POE while on the Q-see you have to buy a separate POE switch if you want to add more cams later on. Also, Swann uses 4mm lens vs the 6mm lens on Q-see.
On paper it seems like swann will have better picture quality, but the actual recording quality and reliability wise? dunno till people try it out. Another thing is that the cat5 network cables are shorter 60ft vs 100ft on the q-see.
I think I'm going to try the swann, not much to worry about because of easy 90 return policy and long costco warranty. I think 3yrs warranty, right?