bitsnbobs, sorry to be off topic but which make of powerlines do you use as mine drop the connection every so often and I have to switch them off then back on again to re-establish it...
I do not use them, my whole house is hardwired, basically downstairs is where my main modem/router is plugged into the phone socket. Off that is a switch running off port number 4 of my rubbish homehub 3 see everything is gigabit. (ultimately at some point that will go and hopefully be narrowed to a single box solution).
From there patch wires feed to an 8 way and 4 way wall sockets, from them the wires go up to each level of the house (3 floors as im in a town house). To wall plates in the appropriate rooms.
On the second floor in addition is a further switch for any future expansion (never know when i might want another NAS for example) and on the top floor i currently have an old router plugged in with DHCP disabled see that, basically just acts as a switch if needed and an additional wireless point to ensure the house on all levels front and back get good coverage for when i have to use my mobile or tablet online. The top floor with just the homehub the wireless gets flakey (50% signal or less).
There is nothing better than hardwiring your home if you plan it properly (draw a diagram of what you want and add at least one additional RJ45 outlet to each room you plan to hardwire).
Its a single day job, a couple of hundred metres of cable along with some RJ45 wall plates, it will perform better and more reliably than any wireless and cost you a hell of a lot less than looking for some £!50+ holy grail device that does good wifi.
If you file share between machines, backup between them, media serve or have any type of NAS things suddenly become a joy to use rather than slow frustration which wifi brings. Copying files several gigs in size between machines on a gigabit network is a joy compared to a nightmare on wireless.
Latency half of what wifi has for gaming ultimately just a bonus as i do not game regularly anyway.
HOMEPLUGS if you must use them will perform (and i do just mean performance not reliability) better than wifi, you only have to look on smallnetbuilder to see that. There only issue is if wiring is old or you have lots of stuff constantly on drawing power speeds will often reduce or connection occasional play up.
As to what ones i would use if i had to id take a look at Solwise they seem to have reliable devices, a whole bunch of good FAQ and general info on their site and also appear to be a good company to deal with. Its important you match the homeplug with the rest of your network and where possible do not mix and match homeplug devices that just causes more issues. Oh and forget about the ones that also have wifi built in/act as access points as that will only be as good (at best) as what is coming out the homeplug end.