Let the hive mind of Engadget get that for you.
"I finally got a new laptop with a lone USB 3.0 port. I'm now looking at getting a USB 3.0 hub with a power adapter so I can use both of my USB 3.0 hard drives at faster speeds. I've read lots of horror stories where some hubs either don't come with power adapters -- and as a consequence the portable drives don't work with them properly -- or they are designed poorly which results in USB 2.0 speeds. Or, the hard drives keep getting disconnected. Do your readers have any suggestions or experience using USB 3.0 hubs? Thanks!"
Having been connected to the industry for some time I'm not even slightly surprised
Average cost to the retailer for 6 foot Monster cable of any type.
$6 or less
Average cost to the consumer
$60 or more
Average margins for store branded cables are the same or worse.
When in doubt, that pimply faced clerk knows nothing. They probably got hired yesterday and stuck on the floor this morning with their only training being "Sell our 'services' and attach top dollar accessories, our customers leave spending less than they intended to, don't let them"
Do your homework, price shop online first. Be sure you know enough to know if the sales clerk is full of crap, just because they aren't on commission doesn't mean they have no hidden agenda.