I'm a long time BF fan, loved BF3, but BF4 was a fail from the beginning. Beta was unplayable, there was some kind of glitch that made it run below 20fps on my PC, they patched that, I bought the game and had enough of it after 2 hours. Netcode sucked, few weapons were so bad it was hard to kill a standing target (e.g. first engineer weapon), the only thing I found to be better in BF4 were sniper riffles.
Graphics and sounds are great but the game is almost unplayable, unless you sit in tanks or snipe, so I went back to BF3 just to find out there's a lot of people still playing it. All my friends play BF3, even though they bought BF4.
actually i found BF4 beta to be more playable compared to the release version. no lags, no dc's.