The thing I really didn't like about Razer Synapse is that it has to be running in the background to control the mouse lights and whatnot. I think the mouse speed settings hold though.
Frankly, does ANYONE like LED lights on their mouses? As someone in a dinky apartment with my office and bed in the same room, I have to physically cover this crap up when I go to bed. lol, too lazy to dismantle things and take the lights out... just wish you could turn this junk off with a simple button or whatever.