Got my first SBricks a few weeks ago and am totally sold! I've already tried them in over a dozen existing MOCs, and every one of them benefitted in one way or another -- especially the working RC boats like the ones below (see http://www.moc-pages.com/folder.php/178225 for more).
For example, the triple-screw boat above is very fast, but the PF RC system severely degraded its play value, as it made the boat nearly impossible to control -- mainly due to latency, lack of range, and lack of a suitable control interface. However, a single SBrick and the Android dual joystick profile made precise control a snap.
I was also recently surprised to discover that my old 9V LEGO train transformers put out power in 5 discrete steps, not continuously. That makes SBrick the only continuously variable power source readily available for MOCs.
Jeremy
XX