I have a PS3 for kids and grandkids to play when they visit. From new, have had flaky wifi, even when in the same room as the router. Eventually bought the above Solwise product, after reading many reviews, and have not looked back since. Can now watch BBC iPlayer in HD without a glitch.
This is a late 70's house with one 13 amp ring main for both floors. I would not know if the 500AV would work from one ring main to another, if, say, there was a separate ring main for each floor, each with its own fuse/rcd. But for my situation, definitely 5 stars.
The main fusebox (consumer unit) provides a separate fuse to the garage, which goes through a separate RCD and fuse box. The Solwise 500AV connects with the unit attached to the router without a problem, but the connection quality is down from green to red. However, Youtube videos can be watched, whilst the OS is updated. Given the circumstances, I again give five stars.