I often buy these on price-alone basis. I love believing the more expensive units can do more, but now they're becoming so ubiquitous that I've found the cheapest units to match their pricier brethren. And Powerline units either work or they don't - it only takes a few minutes to find out. (Which is nice - no need to waste time screaming and yelling and name-calling them - they never seem to mind that.)
There is no guarantee in the technology OR this particular device - or any of them.
I believe every electronics product has a Constitutional Right to die when THEY feel like it, to be sloppily manufactured, dropped and drowned in shipping, kicked off of a top shelf in a mile-high warehouse, left on a scorching metal liftgate, and have shipping crews mistake the dust-bin parts for A-Number-One's.
But for these parts, I buy locally so I can easily drive over and return them. I calculate that I'm paying a slightly higher price for store-parts, so this is MY Constitutional Right to return parts that don't work FOR ME. Stores accept this, too, so it's a nice partnership.
Powerlines will work in your environment, or they won't. That's a blessing in a way - no need to spend hours fiddling and adjusting. No need to scratch heads or wade thru menus of unclear choices. These are one of the most efficient-to-test products around - you'll know in 5 minutes if they're going to work FOR YOU, in your environment. No one's assurance is worth a typed pfennig compared to your experience.