life span of a DSLR
I think you'll find that the basic module of a Pentax DSLR (for example the *istDS leading to various similar models) actually has a market life span of rather longer. If you don't rename and upgrade the models in a range then sales fall off I would imagine.
Canon and Nikon and other models have a similar or even shorter "market life span" so I'm thinking you may have misunderstood what you were being told?
Best regards, John

You will probably find that the MAJORITY of cameras available 2 years ago have been superceded by newer models...Most, if not all, brands update their camera ranges every 12-18 months or so...
If you use your argument as a basis to buy an EOS 50D over a K20D then let me tell you that the 50D replaced the 40D after that had been available for only a short period.. Imagine how cross you would be, buying a 50D only to discover that Canon have launched the 7D

Your heart will be warmed by the fact, nevertheless, that there are many people here who are still using their *ist D models
Z-1p, K-1, P50
F50 1.7. FAs 24, 35, 50 1.4, 85, 135

Metz 45 CL-4, AF500FTZ. AF540FGZ.
Some Mamiya and some Nikon
However, most models and brands of DSLR should see many years of service. Now that the megapixel race seems almost over, technical obsolescence may not be such a big thing in the future. It isn't many years since 1mp cameras were impressive, but now 12 and 15 mp is the norm.
With Pentax DSLRs the original 6 mp istD is still changing hands. The only problem with DSLRs and the later film SLRs ( of any brand ),is that for repairs, the electronic circuit cards and lcd's may become no longer avaiable. This could apply to Pentax, Canon, Nikon, Olympus, Sony etc etc.
Friendly Regards
Graham
Glenfinnan and Polnish Church.
Couple of mates of mine (professionals at ShedPix) have two 50D's that they want rid of, they are not happy with them.
Regards
When something goes wrong in the circus, they send clowns into the arena to distract the audience.
Fact of the matter is that your Km will very likely go on to give you good service for many years to come (if you so desire). I happen to think that the Km is a very capable little D-SLR (we bought one for my eldest daughters 21st and she absolutely loves it)

Regards Huw
flickr
My Dad has a Pentax EI-200 which as far as I know still works fine while being around 8 years old.
Skoda have stopped making the Fabia I drive, but that doesn't make it any less of a reliable runabout.
you don't have to be mad to post here
but it does help
I just cast my eye down the list of manufacturing dates for Pentax film SLRs. Few were made for more than 2 to 3 years. Notable exceptions were the MX (nine years) and the LX (21 years!, although in slightly different forms).
If you compare this to phones or ipods and the like, the turn-over is no greater really (maybe even less). New models have to be bought out on a regular basis to complete.
K.
Kris Lockyear
It is an illusion that photos are made with the camera… they are made with the eye, heart and head. Henri Cartier-Bresson
Lots of film bodies, a couple of digital ones, too many lenses (mainly older glass) and a Horseman LE 5x4.
My website
B. R. Foster
Market live span has nothing to do with life expectation, not for cameras, not for cars and fortunately for me not for people.
If you want to change brands just do it, you don’t need to excuse yourself or are you looking for a good reason to convince yourself to spend all that money on a new system?
Jackie H
K7, K20D, istDS, Optio SV, ME
Most used glass
50mm f1.4, 60-250mm, 28-80mm,
Sigma 105mm 2.8 Macro & Bertha 50-500
Dodging and burning are steps to take care of mistakes God made in establishing tonal relationships. - Ansel Adams -
http://www.valuebasedmanagement.net/methods_product_life_cycle.html
B. R. Foster
Having just had an email from Pentax ,I asked why do entry level cameras ie K100d, K100d super KM and Now Kx called Entry level, as to me Pentax seem to build more so called entry level camera's than anyone else.
I was told by Pentax , that any DSLR including pro has a market life span of 1.5 years max. That's cleared that up then I won't be saving for a K20d, I buy a Canon Eos 50d, as my 400d is still mentioned & Loved by canon users. cheers Pentax I'm clinbing of the merry go round.
...............and your car has a market lifespan of between 6 and 12 months.
Hyram
Bodies: K20D (2), K10D, Super A, ME Super, Auto 110 SLR, X70, Optio P70
Pentax Glass: DA* 300, DA* 60-250, DA* 50-135, DA* 16-50, DA 70 Ltd, FA 31 Ltd, DA 35 Ltd, DA 18-55 (2), DA 12-24, DA 10-17, M 200, A 35-70, M 40, M 28, Converter-A 2X-S, 1.4X-S, AF 1.7, Pentax-110 50, Pentax-110 24
Other Glass: Sigma 105 macro, Sigma-A APO 75-300
Flash: Metz 58 AF-1 P, Pentax AF160FC ringflash, Pentax AF280T
Paulm0bsw
Member
I was told by Pentax , that any DSLR including pro has a market life span of 1.5 years max. That's cleared that up then I won't be saving for a K20d, I buy a Canon Eos 50d, as my 400d is still mentioned & Loved by canon users. cheers Pentax I'm clinbing of the merry go round.