Sigma or Tamron 18-200mm?

I'm looking to buy either of the above lens for my brother who has recently purchased one of the refurbished K100D Super's from Cameraworld. If I could stretch to the Pentax 18-250mm then I would no problem. Has anyone got either of these lenses and if so which one gives the better results?

Thanks

Rob

The pentax 18-250mm is currently being advertised at a reduced price as the lens is now discontinued. It's a good lens, nice and sharp, but suffers from a very small maximum aperture (f6.3) at the longer end. That and its bulk are the only real drawbacks.

i got a tamron 18-200mm and love it, its the only lens i use, take a look at my portfolio pics.
its well built and opticaly very good, great colour and sharpness, i got mine at bristol cameras for 169 delivered.

also tamron do an 18-250mm which is very good, but the 18-250mm are lots more expensive, and the sigma 18-200mm is about £200 and the tamron cheaper bristol cameras is the cheapest i found, hope this helps.

Thanks for the advice. I have the Pentax 18-250 myself and agree that it is a cracking lens but even the reduced price at the moment is too much, having seen the image above I shall look around for the Tamron then. By the way what body do you use the lens on?

Rob

i have a k200d but i had a k100d super before. you wont be dissapointed
with this lens.