I bought Lego EV3, and plan to use Lejos project.
I follow the very good Getting started with leJOS EV3 howto to create SD card, configure eclipse and so on.
But it’s very boring to turn off EV3, copy program to SD card, then restart EV3 to run it.
As explain in Creating a bootable SD card howto section, using a wifi dongle improve greatly those steps.
However, setup wifi connection using EV3 is really annoying, especially if you use a complex PSK, and impossible if you use hidden SSID.