I played around with the Ferox last night, completely stripping its fittings and starting over working from the new 250mm Prototype Guass railguns up. Those rails are better than the Tech 2 versions except that they cannot use the Tech 2 ammo. Once I got the weapons on I worried about tracking enhancers and computers, sheild resists, etc. In the end I had a ship I felt could deliver a decent punch at range, maintain capacitor charge, and has a small passive shield tank.
I then played with the different ammo types to see what ranges I could get. With Antimatter my optimal was about 20 Km which wasn't stellar because anything getting closer than that to me gets such a high transveral that I can't hit them. (Hmmmm, forgot about trying a webber...). Midrange I tried out Lead and got up to 41 Km which is much better although the damage is less impressive. Finally, at extreme range I have an optimal of 66 Km when using Iron ammo. Least amount of damage but able to hit early and often.
My strategy with this ship fitting appears to be to try and start 99 klicks from my target and use the sensor booster to get an early lock. With a falloff of 12 klicks I activate my rails when they are about 80 Km out and I try to maintain distance of 66 Km. Once they get to about 45-50 Km from me I switch ammo to the Iron and get more damage per shot. Then when they are less than 30 Km finally switch to antimatter and go for the big damage. If they are still coming and near death, I'll finish them off with the drones and light missiles from the assault launcher. If they are not near death, I bug out.
Obviously this isn't going to do me any good one on one PvP because if I'm winning they are going to leave before I kill them and if I'm losing I have to run before they scram me. But as a support ship, I can warp in and target something quite far away and provide decent fire support.
Now that I have a Ferox build I like (realized that the sheild rechargers were draining my cap so much nothing could recharge; once I removed those my cap issues disappeared) I'm very excited to see how it improves as my skills do and I can't wait to get into the Rokh.