digitalCG wrote:
Aha, now you're talking You won't have too many issues with that setup, I have the same and AF is pretty good, AF-C is quite respectable too.

Aperture-wise it depends what you mean by 'small'. Remember that a small f-number actually means a larger iris opening. Put simply, the lower the f-number you use, the more critical focus becomes. This is especially true if your working distance is quite small, i.e. your subjects are whizzing by pretty close to you.

f8 is generally quite safe, f5.6 okay and you'll notice anything less than that becoming increasingly tricky. Take a look at the exif data of some shots you like and see what effects the varying apertures have.

As for shutter speeds, aim to keep your shutter speed high, 1/250 or faster at first, then as you feel more comfortable begin to vary it and experiment some more.

Good luck and let us in on the results, the K5 is a much better tool for this than any previous Pentax DSLR