You are always better sticking to one brand for wireless repeater.. since apple cannot extend dlink wireless nor the dlink the apple wireless, you are far better keeping wireless just apple or dlink.
Powerline adapters are a good method to avoid the issues with wireless repeater.. namely extremely slow wireless.. since repeating wireless adds huge amounts of latency into the wireless connection.
Problem with powerline (EOP) is they are dependent on the house wiring and it varies from house to house. Just like wireless it is not able to give guaranteed throughput (only ethernet can do that). It some cases eg wiring on different circuits that passes through a set of breakers.. will simply not work at all or so poorly as to not fix the problem. But if you have the two points on a ring main where there is a direct wired connection it can work extremely well. It will end up far more robust as it is not subject to the same level of voodoo and gremlins as wireless. ie if it works well the day you install it.. it tends to keep working the same thereafter.
So there is just one way to find out.. buy a pair and try them. You must use a power point.. no powerboard as the current breaker on the power board kills the signal. Some models come with piggy back connectors.
At the other end you can setup another wireless router in bridge and create a roaming network using the same SSID as the main wireless.. this then stops the confusion. Albeit roaming does not always work as well as the name suggests. Some devices swap "towers" with ease .. just like your mobile phone.. whereas others attach themselves to the AP they first connect to and refuse to disconnect. (without a swift kick at least).
Your Dlink could be made more home friendly by using roaming as well.. to prevent having multiple SSID. But the quality of repeated wireless is still poorer than single point AP with wired connection.
