The G502 is touted as one of the best out right and I can totally agree with that. Honestly, I dont myself changing mouse any time soon. The feel of it and build quality is awesome. The grip on the sides and optional weights is great.
As for the optical sensor, everything has been on point as it should be. No weird lags or stutters.
Among the best of sensors. Straight raw, no acceleration like laser mices tend to have.
As for the look, I too wasn't a fan of it in pictures, but that changed once I got it. The lights are all customizable too so if you want them off, that is an option.
To note, Logitech also has great warranty for the time I dealt with them.