Shame there's no strap........kinda pointless without one

Just spotted this one:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&category=4688&item=3871986093&rd=1

I want one too!

I have the 1.7x AF adapter and can't fault it, particularly when used with a quality prime lens.

Thanks Mike, I've got the original FH-80 - excellent for a budget priced gun!
I've used it on both my SXF and Z1-P and was 99.9% sure that it would be ok on my *istDL but haven't tried it yet, thanks to your reply the 0.1% doubt has now gone

With regard to 'red-eye', although the SFX-N's built in flash does not have a red-eye reduction mode, the hot shoe is positioned on the hand grip and is therefore slightly off set from the lens' axis. This helps to reduce the incidents of noticeable red-eye.
It might be worth picking up a cheap Pentax dedicated flashgun (preferably with zoom and tilt head) and/or extension lead and bracket to further increase the distance. You would then have a highly versatile system and can use both the built-in RTF and external flash simultaneously if you wish.
This could prove to be a cheaper alternative to a second camera body and would provide you with many exposure mode options and you could experiment with flash sync techniques.

Pentax guns are of high quality and are correspondingly expensive but you could find a bargain or two on eBay. Most manufacturers have Pentax dedicated models and they should all do a decent job and probably be quite a bit cheaper. Any dedicated manual gun will work but you should look for an AF model as it will send out a near infra-red beam to assist the camera's focussing in low light, just like the RTF.

In any event, it's useful to have a second camera body but the SXF-N may turn out to be more versatile and effective than you imagined.

The MZ-M is the UK version of the ZX-M, a great camera for the price but a tad too basic for me. The SFX-n is more capable albeit without multi-segment metering but the ZX-M is only 2 segment anyway and not that much better than centre-weighted.
Personally, I'd look for a P30T or Super A (or whatever their US equivalents are called!)
It's a pity that Pentax didn't produce a manual focus camera with 6 or 8 segment metering + spot and built in flash, but I guess that would be a Z1 in manual focus mode!

If you're not too bothered about size and weight, the Z1 or Z1-P would offer far more advanced features than the SFX, approx the same size/weight and full manual control when required.

I've often thought about picking up a manual body myself, but can't really see the point when all I have to do is switch off the AF mode etc.

Not quite sure what you're getting at there, David.
Most zoom lenses quote two maximum apertures ie. 3.5 / 5.6 (to use your example), this means that the maximum is f3.5 at the shortest focal length (toward wide-angle) and f5.6 at the long end (toward telephoto). This is because you lose light as you increase the length of the lens. A 'fast' telephoto would have to be very large (diameter) and therefore heavy and expensive - such lenses are designed for specialist use and carry a professional price tag.

The lens only stops down to the aperture setting chosen, by the camera or the photographer, when you fire the shutter. This enables you to see the subject clearly up to the point of exposure. The depth of field preview function found on some cameras, enables you to close the aperture down to the setting that will be used for the final exposure so that you can see how much of the foreground and background will be in focus for the actual shot.
Obviously, the image seen through the viewfinder will darken as the aperture closes but it gives you a very good actual view of the depth of field. Some cameras feature a graphic representation on the LCD display and / or in the viewfinder and you can refer to the depth of field scale on the lens eg. you know how far away the subject is because the lens tells you, you then look for the distances before and after the subject distance as indicated by the aperture markings on the lens barrel.
If you look at your 50mm 1.7 lens (I'm presuming autofocus F series), focus at 1m and you'll see three white lines marked 22, 16 and 5.6, the depth of field extends from 0.8m to 1.5m at f22, approx 0.85m to 1.3m at f16 and 0.95m to 1.1m at f5.6 (you can calculate the precise figures if you wish or refer to pages 52 and 53 of the SFXn manual).

For cameras that don't have a depth of field preview function, there is a way to cheat - set the aperture and depress the lens release button, then very carefully turn the lens (approx halfway) as if you were going to remove it. The aperture will stop down to the setting you chose and hey presto you have a preview function!
As the lens is effectively half removed from the camera at this point, be very careful not to allow it to fall off and remember to re-fit it properly.

BTW, the sub-modes I referred to previously are actually called 'wide' 'standard' and 'tele' - sorry for any confusion.

Lenses with KA mounts display the aperture setting on the CENTIC panel when the aperture ring is set to A (automatic), when in Program and Auto mode.
It is not necessary to display the aperture in other modes, you would know what it is because you set it yourself.
Your Sigma lenses should also display the chosen aperture when set to A in Program/Auto mode.
My Tamron lenses perform exactly like A series Pentax lenses, the F series zooms however also enable the SXF sub-modes to come into play (automatically selecting depth, standard or action - based on focal length) but the camera cannot determine the focal length of the Tamrons because of the interchangeable mount. I can change from a wide angle, to a zoom, to a telephoto and the camera wouldn't know the difference but you shouldn't have this problem with your Sigmas unless their built in chips are not as sophisticated as the Pentax ones (they may only provide aperture information and not focal length).

I've tried my SFX with Pentax A, F, and FA series lenses as well as the Tamrons with KA mounts and none of them display the aperture setting on the CENTIC when the aperture ring is moved away from A (or AE).

I always think of F-stops as fractions ie. the bigger the number - the smaller the hole!

Pentax manuals have charts that show graphic representations of the relationship between apertures/focal lengths and depth of field and also how these shift with regard to the program modes.