If anyone would like to send me a pair of PLA's i'll test them and make and observation on how it effects the broadband or not and then send it back postage free
I've got a spare pair not in service and currently surplus to requirements, I'll look them out and see whether they're of interest to you.
I'm also interested in your comment about TP-Link, I have two TL-WPA4220 and one TL-PA4010, and my tentative tests suggested that they did not have any impact. They're out of service at the moment but removing them didn't seem to change either SNR or error rate.
I tried every home plug going some years back and always ended up with millions of FECs and a lost connection just plugging them in and switching on let alone trying to actually connect. Tried some wireless Devolo homeplugs and same problem so gave up.
A few months back while at someone else's house trying to sort out some wiring, I spotted they had some I'd never seen before. And they had a spare pair so borrowed them expecting the usual failure. But no, they worked flawlessly without the slightest trace of any noise above my floor level of around 300-1000 FEC/min and certainly zero affect on any other stats.
So bought a pair of my own and have been using ever since.
They are BT products (Broadband Extender) but don't know who actually makes them but they are very different appearance-wise to others.
It may just be my setup here but nothing in the wiring or equipment has changed since trying the previous ones.
The ones I have are these:
http://www.shop.bt.com/products/bt-mini-wi-fi-home-hotspot-500-kit-079029-9N14.html?refs=50910They do make a 'larger' (Dual Band) version but haven't tried these.
I do have a spare master plug (the one on the left). I'll see if I can pick up the other one somewhere and can then loan that if you like..