Powerline are not "better" than wireless it really depends on your situation and your house. Wireless tends to be faster but also tends to be more susceptible to interference and many times is blocked by walls in the house. Powerline is said to be better for games because it does not get as much random packet retransmissions.
There is not a huge difference between brands. There are pretty much 3 speeds 200,500,600....I think there is a newer one but I have not seen it.
I would avoid the 200m ones the newer 500 and 600 tend to be much more stable as well as delivering more speed. The difference between 500 and 600 is not a lot so only you can decide if the extra cost is worth it.
Most people get in the 70-80m speed on the so...