Which circa 200mm

I'm thinking about getting a lens in the 200mm range, to slot between the DA* 50-135 & 300 lenses I've got.

My thoughts at the moment are:
1) Pentax DA* 200 F2.8
2) Pentax DA* 60-250 F4
3) Sigma 70-200 F2.8

I want something with reasonably fast autofocus (suitable for motor sport, for example) and nice, sharp image quality.

The zooms have the obvious advantage of convenience, but having recently acquired the DA* 300 I'm impressed with the results from it, so quite tempted by another prime lens.

What do you guys think about these choices as far as fulfilling those requirements is concerned?

If you can manage with the slightly slower maximum aperture of f4 then the DA* 60-250 is superb, it is sharp at maximum aperture (many of the superfast zooms in this sort of range aren't) and has the benefit of WR (good for MotorSport?) - the only downside I can see for you is the potential that you may never use your DA* 50-135 again - thats what's happened to me

Sound advice from LennyBloke.

Yes, I did think that if I went for the 60-250 there's a good chance the 50-135 will have to go - partly because of the overlap and partly to help fund it!
The autofocus on the 50-135 is fine for everyday use, but is slower than the 300. It's certainly quite usable for motor sport, but the 300 is definitely better. This is why I was wondering about the AF speed of the 60-250 & 70-200.

I have the same pair, DA*50-135 and DA*300 and when I bought them wondered if I should get a DA*200 but decided against it.

I have never found myself saying "I wish I had a 200". Yes at 135 the object may be slightly smaller but at full resolution and cropping the differences are minimal.

I do also have a DA50-200 and 70-210 but apart from checking they work together have never been on my camera - they stay with the old *istD and MZ-S.

Unfortunately I have missed that part of the range on a few occasions (eg motorsport and falconry displays), and it's not always possible to move backwards/forwards.

The 60-250 is certainly my preferred option in terms of the range on offer, provided the AF speed is good enough.

I did try a 60-250 on the day I bought my 300, and was disappointed with the image quality. But it was a hire lens, which seemed in need of some adjustment, and there wasn't another one in stock for comparison, so I think I was unlucky with that particular lens. The 300, on the other hand, just blew me away with it's sharpness after comparing it to the 60-250 and a Sigma 150-500.

I have the 60-250mm f4 and Sigma 70-200mm OS f2.8 (and have had the DA* 200mm f2.8 ). If you were disappointed with the IQ of the 60-250mm then all I can say is you must have had a duff lens because mine is superb straight from f4 and the range is very handy. The only thing against the Pentax zoom is AF speed (although it is much better on the K-5/II). For out and out quality though the DA* 200mm is the winner, just brilliant IQ but I felt limited by the one focal length so it had to go (although I must admit to being tempted by the ones presently floating around for sale.

The Sigma is a sort of halfway house, AF speed is excellent, IQ is not quite as nice as the Pentax 200mm but unlike the 60-250mm it has 2.8 (which is very handy at times and more than passable). But then you have the 50-135mm for 2.8.

I have always said .. if I had to sell everything and keep only 2 lenses it would be the 17-70mm f4 and 60-250mm f4

Mike-P - I think what you say about these lenses seems to pretty well confirm what I have been able to read up about these lenses. Although the Sigma seems to have good AF, the quality on the two Pentax lenses seems to be better. I know I would probably regret not going for the sharper lens,
so I suspect I'll end up choosing between the 200 & 60-250.

For out and out quality, you say the 200 is best. Just how close would you reckon the 60-250 is to it?

Difficult really because I tend to shoot everything wide open if I can and the extra stop does make a difference (for me at any rate). TBH I think the extra focal length is worth the slight drop in IQ, especially with the K-5/II/s being so good at high ISO.

Edit: I don't think the Pentax lenses are sharper than the Sigma, just that they seem to output a nicer looking picture.

Another thumbs up for the 60-250

Thank you all for some constructive advice and comments.
Out of the 3 I was considering, I was already favouring the two Pentax lenses, with a slight bias towards the 60-250. Opinion seems to be mainly in favour of the zoom, so I think that's the one I'll be aiming to get, unless a real bargain presents itself for a 200.

Not if I see it first