Very distinct and abrupt change in average performances. Went from ~1k/d to consistent 3-4+. Don't think it's an aimbot, probably wall hack of some kind. Noticed him in this game:

http://battlelog.battlefield.com/bf4/battlereport/show/1/1019035026490677248/947466896/

Would consistently prefire and 180 on people with no apparent knowledge otherwise.

A few more sketchy ones:

http://battlelog.battlefield.com/bf4/battlereport/show/1/1018563951142270784/947466896/

http://battlelog.battlefield.com/bf4/battlereport/show/1/1018042058043717440/947466896/

http://battlelog.battlefield.com/bf4/battlereport/show/1/1018178233173702464/947466896/

http://battlelog.battlefield.com/bf4/battlereport/show/1/1018045563177432896/947466896/

http://battlelog.battlefield.com/bf4/battlereport/show/1/643922530929959360/947466896/