Dont bother to upgrade LF-4's as you want to get the Prometheus lasers. Bot ABG for x4 ammo and then once you've got 400-500k head on to x-BL Map (depening on your firm obviously) and only kill Impulses (Vertex and use 711 distance) on Drill with like 100k sheild full speed pref. with Cyborg or Solace (with the ship gear, buy it on shop). Gives 15% more dmg to NPC's.
Once your x4 is low and you've saved all Uridium, you'll need alot more x4 and also BK's as the blueprint for Prom lasers costs 75 BK's each. Bot Zeta Gate on sundays and ABG once again for more x4. Doing it right you should be full Prom after 1-2 months.
