Originally posted by KxBlaze The K5 is better for every single photography job known to man. The camera is just that much better than the Kx or K7 so definitely go with the K5.
I agree with this as well. I have the K-7 and have shot some indoor basketball and I felt I was being limited by the camera ISO. I don't like the K-7's noise above ISO 800 and I resorted to shooting with my FA77 f/1.8 and was still having to push the ISO to 1600 to reach a compromise between motion blur and ISO noise that I could handle. But this scenario is tough with any APS-C sensor. Ideally a FF camera matched with fast glass would be what you would use.
Originally posted by hcc Ultimately the lens selection is probably more important.
I think your right on the money. As Halving the f stop gives the same result as quadrupling the ISO from memory. So if you shot a scene with a f/5.6 at ISO 1600 you could shoot the same shutter speed with a f2.8 lens at ISO 400. Huge benefit in Noise. Or from another perspective you could get a lot more flexibility with Shutter speed.
But At the end of the day It all boils down to how much money your willing to throw at it.