The only fun & deadly build that works well is 4xAC2s + 2xAC5s on the MX90. It manages heat better and this combo has the killing power that 6xAC2s lacks (18 vs 12 per volley).
My conclusion is that the poor AC2 needs a buff to make it a viable weapon for MWO because it needs to be run in pairs for any effect. Given that your damage more than doubles for only 2 extra tons with that AC5, AC2s really only work when you need to save space (but then better to equip a laser) or when bundled.
The high rate of fire works against you when you bundle them due to the quick heat build-up so in the end it requires more heatsinks and thus space to run them compared with AC5s.
So PGI, please make it slightly more powerful to give it a good chance in this game. I suggest something between 2.5 - 3 damage per AC2 shot and consider dropping the heat to 0.5 - 0.7 per shot.
Edited by Jman88, 29 September 2015 - 10:03 AM.