My Netgear R7000 has the feature you want. http://www.smallnetbuilder.com/tools/rankers/router/view

Hi, Unfortunately, the TP-Link firmwares are very poor and far away from those of Netgear or Asus...

Only the device !

mlhifi wrote They have now said I was right and that the bandwidth can NOT be adjusted. It automatically detects the intereference in the local area: Litte interference and it operates in 40mHz...

Hi, Is there any difference when the channel bandwidth is set to 20 or 40MHz?

Hi, Probably, but keep in mind that each time you're repeating a wireless signal you're dividing the throughput by 2...