If you want to go with 4xMG, full armour, and full jump capability, a MPL is the biggest energy weapon you'll be able to fit:
4MG+MPL.
If you're like me, you won't mind sacrificing some armour and jump for the added range and punch of a ERLL:
4MG+ERLL
I tried the AC thing before the MGs got buffed, and it just doesn't work for me.
AC/2 + ERLL was okay even though it was on the slow and fragile side, but the heavier ACs precluded an energy weapon or left me without jump jets.
Either way, the MG is in such a good state now you can have loads of fun with one of the quad MG builds, there's no need to try and mount a heavier ballistic in the Spider.
Edited by stjobe, 16 August 2013 - 05:12 AM.