I'm on 8 ping, 120 download, 25 upload and while I often have 4 bar it makes very little difference to actual gameplay for me, I still get major lag/lag comp. Lately the lobbies have been fluctuating a lot more though, losts of 3 and 2 bars about.
Sadly the game's connection quality simply isn't up to previous titles, try BO1 with a fraction of the number of people playing and you'll see how it should play