Which lenny to choose!!!

Hi All,
I am due a bit of a bonus in the next few weeks and so I wish to try to satisfy my LBA and be able to shoot the karters at my local karting track so fast AF is essential. Also I recently sold "my precious" Sigma 105 macro and need to replace it, I also what to satisfy reach so 500mm is on the list.
Here are my options (please bear in mind for ultra close up I have the tubes and a 50mm)

1. sigma 70-200 f2.8 macro + sigma 150-500 (Reach + fast but iffy on macro)

2. DA*60-250 + Pentax 100mm macro WR (weather proof solution but no reach)

3. Bigma + Pentax 100mm macro WR (No mid range)

If fast AF is essential then the 70-200mm is the only choice out of that list.

Cheers MikeP, so on the K-5 would the 60-250 be much slower AF than the 70-200?

option 1 for me. both are as quick as each other for af speed.

I steer clear of Sigma HSM lenses because my Sigma teleconverters will only work with their screwdrive offerings (70-200mm and 100-300mm)but I have tried a couple and they certainly felt faster than the 60-250mm.

Must admit I haven't tried any on the K-5 though but I have a Sigma 50-150mm coming tomorrow so can test against the 60-250mm if you wish.

I guessing that would be a definite yes. SDM is silent but it isn't anywhere near HSM for speed. I tried the DA*300 and 60-250 side by side on my K5 last week .... 300 was definitely faster and the 70-200 is supposed to be, and almost certainly is, faster still.

Thanks for the replies guys, and yes Mike I would love a comparison between those two, thanks.
And cheers froggy I will bear that in mind.

I've just found this too link Towards the bottom of the page the op mentions that his Kenko 1.7 TC works with these lenses, I have a 2x ... I hope he's right...