I don't use any of them. Still prefer the good old closed metal box for a PC case. My keyboard actually has programmable RGB for each key. But this pretty soon got boring to me. Only have the whole keyboard on solid blue.
Definitely tempted to go this route since I want to upgrade my ram and the ripjaws with me rgb are honestly really cheap for the speed right now. And my keyboard is the same lol just not blue
I haven't tried signalrgb, but openrgb is good enough for me. I've set it up (with some plugins and additional .json manual editing) so that my CPU fan is a separate zone that goes green-red according to CPU load, and the rest of the fans have a nice swirling blue-purple color. It was a bit of a pain to actually manage to split it like that, but it works very well and looks beautiful, so ain't touching it any more :)
Do you notice it taking up notibal recourses (cpu mainly). I have signalrgb and I notice it sometimes using more than I want cpu usage wise. Might be because it is doing an audio visualizer. But the temp thing is really cool.... I actually would rather have that.