Firstly, it was very bright and sunny, so there was no danger of having too low a shutter speed to not capture the aircraft sharply.
At F8, I think most of these were around 1/1000th second, using ISO 200.
I kept the camera in Aperture Priority just to maintain the optimum sharpness at F8. All of the pictures I posted were using the 70-300mm lens, and mainly in the 200-100mm range.
I wasn't avoiding using it at 300mm due to a lack of sharpness there (sharpness is still good at this focal length, but not as good as at 260mm down) but due to the fact that the atmosphere was quite dusty and this affected clarity when the aircraft were further away.
Generally I try to adhere to the 'rule' that I've found on various forums about keeping shutter speed at slowest equal to the inverse of the focal length you're using - i.e. shooting at 125mm, then keep the shutter speed at a slowest of 1/125th. Keeping the lens in A mode, with the F number you want, means just keeping an eye out on the shutter speeds and then adjusting the ISO only when you need to in order to keep noise as low as possible and as many keepers as possible.
Of course, using a VR lens gives you a couple of stops advantage, so you could push things down to 1/30th at 125mm, but that would involve panning and losing sharpness, and your number of keepers reducing a lot.
Luckily all these aircraft were jets - it's easy to capture sharp images in good weather by just keeping that shutter speed fast. Shooting propeller aircraft and helicopters makes things a lot more difficult, as you want to get some blur in the blades while maintaining sharpness - you'd need to move into shutter priority ideally at 1/125th to 1/60th and pan smoothly.
I'm a complete beginner at all this though - check out the Mustang Air to Air thread at www.fredmiranda.com/forums
in the City, Still Life and Abstract folder - there are loads of stunning shots in there, and lots of shots where these dedicated guys have got their 'holy grail' of full discs - i.e. prop blur for all 360 degrees...
Here are a few examples at slower shutter speeds, to get a bit of motion blur into the blades, but nowhere near slow enough to get a full disc: