Powerline adaptors work ... most of the time.
They cause all kinds of crud on the radio spectrum, which you may not care about, but many of us do, and would ban them if we could.
The users of that spectrum may be running significant transmitter power, which means your powerline adaptor will stop working when they transmit. You may find this frustrating, but since you are the secondary user you'll have to put up with it.
Cat 5 cable has a lot to be said in its favour. It's also cheaper than PLAs, although it does require some dexterity to install it in houses that weren't designed for it.