At least the OLDER ones are affected by acceleration, Linus sometimes mention that on some of his gaming mice video reviews. I can't say that acceleration is bad or good, it totally depends on the user, if they can handle it without a problem then I would say it's not at all. Meanwhile, most of the top players I know prefer optical/infrared sensor, rather than laser sensor (of course there are exceptions). Which is why I would recommend optical/infrared over laser for the majority of people out there looking for a gaming mouse.
Actually before I had my G502, I was thinking between the older G500s with a laser sensor and the G502 with a newer and more advanced optical sensor. The acceleration factor of that G500s wasn't clearly explained/detailed when I looked it up, so I ended up getting the G502.