I'll agree with Wedge on one point - Ambush should not be a crew skill. That said, I believe that I would remove Ambush from the gunner, even if it meant that the cost of the Skimmer would drop a few points.
However, I disagree with the fact that a gunner would not wait for an opportune time to fire, instead of spraying the field as he goes. I believe that a gunner should be allowed to hold an AC on Wait, like any other model. As for being able to fire when they see "the whites of their eyes," I consider that a benefit of having spent a support slot and a chucnk of points to have that moving target in my force.
A vehicle has one limitation that is constantly overlooked:
Firing Arc: According to 2nd Ed., the firing arc of a Skimmer (and most other vehicles' main weapons) is 90š - not 180š. This forces vehicles to turn to bring their weapons to bear, and forces tactical manuevering. Further, if a vehicle takes a critical hit to its Steering, well - it gets even more fun.
If it were to come to a FAQ team vote, I think that I would vote for restructuring. If that was not possible, then I would have to vote to leave it. It is, actually, exemplified as being able to do what has beend escribed as an "oversight." I do not think that it is an oversight if it is specifically defined as being legal.
Wedge, your points are no less valid than mine, and I fully respect them. I happen not to agree, is all, bud.

However, I leave myself open to differing viewpoints, and reserve the right to change my mind if presented witha good argument. You have provided a good one, here - just not quite good enough, yet, in my humble opinion.
I look forward to the discussion.