I was initially very skeptical of th side buttons, but I don't think theyre too bad. They're shaped in such a way that although they're nestled together, it's not too hard to hit the one you want. The triangular profile of the buttons help, and I think alot of the issues people were having came from how you press them. You don't press them straight down like a thumb button on say. the DeathAdder, I tend to sort of sweep them up with my thumb if that makes sense. Its easy enough to do given how they sit.
As for the top buttons, the top two under your left finger are almost shaped like a toggle, and I use them for DPI switching. They look like a pain, but the way they're shaped makes them easy enough to use. The only button I don't like is the one behind the free scroll button in the middle. It's just a bit awkwardly placed to my hands.