I've also got one of the older ones (70-300 APO Super II) and there are usually plenty available on Ebay (min cost about £60). The current model seems to be reviewing well though.

It's a good point about the good prices that can be had on 2-lens kits (especially Samsung ones) however given they're about the same price new I think you'd either have to be primarily interested in the Pentax's small size to consider it before the Sigma which is considerably better in every other way (in my experience and opinion of course!).

When you could get the Samsung version for £50 I'd definitely have bought the 50-200, but it's not worth £170.

It's been my experience that in this case the Sigma 70-300 APO is a much better lens than the Pentax 55-200 for everything except physical size. A total no-brainer to go with the Sigma IMHO - it's sharper & faster throughout the shared focal range (it's a little soft at the very long end although stopping down to F8 helps a lot) plus it has a very useful 1:2 macro capability as well. I've put a few example shots up on http://www.pbase.com/niblue/sigma_70_300

Despite already having an 80-200 F2.8 I've found the Sigma 70-300 to be a very useful lens - a good combination of capability, flexibility, size and value for money.

While it's not my cup of tea I have no issue with someone honouring their departed friends or family in such a way. It's also worth noting that not everyone is against the wars in Iraq and Afghanistan and therefore it's necessary to accept that the viewpoint in such a case is going to be different than that of someone who is against the war.

If this chap feels that this is a fitting tribute to a fallen brother then that's fine by me and I'm not offended by it - despite my personal views being that the 2nd Gulf was was ill-advised. Note that by no means is that assessment anti-American, the other countries involved (including my own) were clearly just as ill-advised and ill-prepared for the aftermath.

BTW I was serving during the first gulf war (although not out there on active service) so can't be regarded as anti-military etc. either.

It's partly the better quality glass (the 16-45 F4 is much better optically that the kit lens, especially with regards to corner/edge sharpness) but also partly about versatility. Although the 16-45 F4 isn't much faster at the wide end than the 18-55 it's much better optically at wider openings.

In addition 16mm is significantly wider than 18mm (equivalent to 24mm v 28mm in the film days) which can also be fairly important depending on your type of shooting (it is for me).

It all adds up (for me at least) to the 16-45 F4 being a very useful lens compared to the 18-55 which I find largely useless.

Having said all that, and depending on your type of photography, I wouldn't necessarily consider the 16-45 or 16-50 if I was looking for primarily a landscape lens. The Sigma 10-20 I find a more useful landscape lens that the 16-45 F4 - and while I like both lenses (they're the two I use most) I find the Sigma is at least as sharp optically as suffers from less CA (not that it's bad on the 16-45) - in fact when I'm out with both lenses the quickest way I can tell later which one was used for a particular shot in the 16-20mm range is by CA, if it has some it's the Pentax, if not it's the Sigma.

My usual long lens is a 80-200 F2.8 with or without a 2x TC but as it's big and heavy I bought one of the Sigma 70-300's (2nd hand - there are usually plenty about) for when I wanted to travel a bit lighter. I've been quite happy with the lens, including at the long end and for macro, considering it's price etc.

A 28-300 wouldn't be top of my list - I'd rather have the Sigma 70-300 APO Macro than one of those.

Top of my list for a new lens would probably be the Sigma 135-400 F4.5-5.6 DG APO (warehouseexpress list it at £410 in Pentax mount).

Buying yet another lens has always worked for me...

I decided to add a few M42 lenses to the collection and the first is a big lump of 135mm F2 glass from Soligor:







And example shots at F2 (I need to sort a spring in the aperture mechanism before I'll be able to stop down):

These days I think all the manufacturers have good coatings. I use a mix of 3rd party and Pentax lenses and have seen no evidence that Pentax lenses are more flare resistant than the others. I've actually been very impressed at how flare resistant both my two widest lenses (Sigma 10-20, Pentax 10-17) are.