I've had pretty good luck with a couple of Powerline kits where one adapter also includes a WAP/Extender. I've used both the Netgear XWNB5221-100PAS and also the TP-Link WPA4220KIT. They're both more reliable in a WAP setup as opposed to a Extender/Repeater since the auto hand-off seems to hold on at too low of a signal going in both directions. That said, even in WAP mode the DHCP and routing is still handled by the router, so there's no subnet segregation.