I'll revise my statements a bit and say that a pair of large turrets and a giant bin of SCBs can give even the best Vulture pilots a run for their money. As it stands, turrets have no good counter, and the Vulture can't carry enough SCBs to go toe to toe with a full shield/SCB Clipper long enough to prevail.
The Vulture's maneuverability is so high that you can make a fixed or gimbaled loadout the the clipper almost meaningless, but there is just no way to entirely avoid the whole top 180 degree hemisphere the turrets can hit.
A Vulture can realistically carry five solid SCB uses. A Clipper can be setup with roughly the same shield strength, if not more, while carrying 10+ stronger SCB uses.
In one on one scenarios (which aren't always common) I still typically win against CMDR Clippers with a Vulture, or force a retreat. I almost always do with my FDL. However, in 1v1 scenarios the best Clipper pilots can always force my withdrawl if I'm in a Vulture and nearly always in the FDL, unless I'm running an extremely high DPS/alpha loadout.
To give an example of a Clipper setup that can perform such a feat:
http://www.edshipyard.com/#/L=603,5TQ5TQ5Rr5Rr0_g0_g0_g0_g,2-9Y9Y7_8S9Y8S6k,7Vs7jw7gy7gy7fO7fO7dq7dq
Keep all the SCBs disabled except the A6; when the A6 is dry, turn it off and enable a B4 and a B2; when those run dry, turn them off and enabled the other B4 and B2; when those are exhausted; turn them off and turn on both B3s. Optionally, you can remove one of the boosters for a heatsink launcher to manage heat if you feel it necessary.
That's twenty SCB uses adding up to more than 4,500 extra MJ of shield capacity. Pulse laser turrets do not do very good damage, but you can fire two of them almost forever with only two pips in weapons, and against a Vulture or FDL, you will almost certainly deplete all of their available shield strength before they do yours. Obviously a similarly padded Python or Anaconda will present major trouble, but those ships are pathetically easy to disengage from in a Clipper.
