All are of course full-frame, unless you set them to crop the JPEGs!

It's not just cameras. I've found Which? reviews on domestic appliances, which is where I'd expect them to be reasonably good, not particularly informed or helpful.

I have one exactly the same - it's a very good camera (and lens), but there are lots of them about so as Carl said above it's unlikely to sell for very much. There's a Classified Adverts section on here that you could try; I'm not sure what the likely demand would be.

Stan

I've not used the light box method, but it does sound a better option than a cheap scanner. I use an Epson V500 scanner, but I think it cost around £300 - worth it for me as I had over 20 years' worth of negatives and slides to digitise, and recently got on to a box full of B&W prints inherited from my parents, some going back to the early 1900s. I still take (and digitise) the occasional roll of film or slides with an ME Super for the different results it gives.

I think slide film works better than negatives for scanning, it seems less susceptible to dust and scratches (or at least easier to repair), and the colours and light levels give more scope post-processing.

Here are two examples:

MZ50 with 28-80 zoom using ISO64 Kodachrome (slide). Original scan 1200dpi. https://www.pentaxuser.com/photo/funchal-from-monte-palace-gardens-78433/large

ME Super with 50mm f2 prime using ISO200 Agfa (negative). Original scan 2400dpi. https://www.pentaxuser.com/photo/dillington-house-24639/large

I have the original DA55-300 and often carry it as a second lens when out walking; it's capable of some great images and I'd only part with it if I had to restrict myself to a single lens. It all depends how you use it; I'd never consider lugging a Bigma about, though if I mainly did tripod/straight-out-of-car photography it would make better sense.

I have the K5IIs, which I bought as an upgrade from a K20 about 18 months ago. As another 'walk and shoot' user I can thoroughly recommend it (and would guess that the slightly cheaper K5 variants aren't much different, other than the improved autofocus on the II/IIs).

Stan

I had the 16-45 in addition to a 24-90, and it was an excellent lens with no obvious flaws. I only sold it when I bought a 17-70 (all Pentax btw) because I found I wasn't using it due to the shorter reach. The main optical difference I noticed was that the 17-70 has a creamier bokeh, and on my K5 it seems to underexpose very slightly in some conditions compared with both the 16-45 and 24-90.

The DA18-55 that came with my K20D. I've never used it since buying a 16-45 (now replaced with a 17-70), but it would sell for so little that it's worth keeping as a spare.

I used to have a K20D which I used with various Pentax lenses (none of them fully weather-sealed) and I occasionally needed to clean dust off the filter, particularly after changing lenses several times in the field (never had problems with dust getting inside the lens). I've had a K5IIs just over a year and, using the same lenses, have not had any dust on the filter; the system for removing it seems much better than the older camera.

I'm still using an FA24-90 as my main walk-around lens, except when I know I'll need something wider (e.g. cityscapes and buildings) when I use the DA17-70. I find certain aspects of the 24-90 slightly better than the 17-70, particularly that it's fractionally sharper and produces straighter horizons.

I would be interested in giving the 18-135 a try, but have been put off by comments about image quality compared with the above two. Maybe if I can find a second hand version for £200-ish...