I use wireless adapter but was told by the guy in store to forget the wireless and buy a powerline adapter,he told me my speeds will be maxed,i did and did tests on all 3 ways i connect and these are the results. I can get a refund but want to know if there is something i have to do to max connection as he said.
what speed did the powerline adapter say? it is a common mistake to read the --mbs as 'megabytes per second' but its actually 'megabits'. for reference, 8 megabits is 1 megabyte every second. So getting one that says 300mbs will limit you to 37.5mbps.
If all you care about is raw speed then wireless is often faster than powerline. If you talk about the quality of the signal though powerline tends to be more stable. You will get much more random short term performance variations in wireless.
The key here is what are you doing with the connection. In most cases speed means nothing. Web surfing using fairly low bandwidth and tollerates errors well so it doesn't matter.
Streaming video uses more bandwidth than surfing but still not a lot but it has some issue with errors in the stream. Games use almost no bandwidth but do not tolerate much if any variation in the data stream.
So the sales guy likely assumed you are like most people who post to these forums and plan to run your games on the network. Wireless many times is unusable for games where powerline tends to work much better...of course nothing is better than ethernet cables.
So you have to look at what your intended use is.
Most times the speed of a connection is pure bragging rights. Almost nobody really uses more than maybe 10m even streaming multiple movies. Only the torrent guys downloading the collection of illegal movies they will never watch tend to be using huge bandwidth 24x7