I think I have decided beyond the Pentax lenses I have now, I am back in almost the exact position I was when shooting another brand. I had a body with a total of 4yrs of warranty but when I went hunting lenses the name brand were only a single year warranty, even the sealed lenses. I ended up with a mix of cheaper name brand lenses that were slepper values because of their IQ combined with the important lenses being frmo Sigma.
Right now I have a 50-135, 43ltd, 77ltd and that is as far as I think I will go. The reason, PRICE...I can buy an Sigma 70-200mm EX II F2.8 HSM lense for $719ish with a 4yr warranty or spend near $1200 for a stop slower 60-250 F4. Now before anyone gets apoplectic over these not being the same class lens...they are. I could compare the 60-250 to my old 55-250 f4-5.6 which cost just $235 a year ago...new.
I will likely opt for the Sigma 100-300 EX F4 over an SDM 300mm for the same reason...4yr EX warranty compared to a 1yr for the Pentax. I do like the IQ of the SDM 300mm and it might end up a coin toss, but having had a very positive experience with the 100-300 before, and the unwillingness of Pentax to warranty their lenses beyond what the same as the big two, concerns me when looking at the sealed lenses being pretty unproven in the longer term. And again, I am not saying the seals are bad or whatever, but rather Pentax has raised prices and in return delivered nothing more than any other company, less when compared to Sigma.
The 100-300 based on my own experience with the lens, though not on a Pentax mount, is that the IQ is essentially equal/close enough to not matter.
My standard zoom is once again a NEW Sigma 24-60 f/2.8 EX over the 16-50mm. And I sense I will end up with another Sigma 10-20mm over the DA* 12-24 f/2.8 and here the difference is the price (<$300 vs. ~$700) and again 4yrs vs. 1yr warranty.
I know the DA* lenses I mention are sealed but to me the premium charges is not worth it over the Sigma options in the same class lenses. When I decided to move the Pentax, one of the major reason was that I would not need to spend $5k-$7k to build a nice lens collection...that is pretty much no longer the case. I can spend about half of that via Sigma. So here I am again giving up the advantage of sealed lenses simply because the price for those lenses have become just to expensive in my book. And right now with the issues of the K7 the whole picture is really murky for me, maybe not for you but this is how I am viewing the situation at this microsecond.
Still, I would rather stay with the Pentax bodies as I like the sort of shots they deliver and I will be adding the 31ltd silver just to complete the set...

But I do not see myself buying any firther new Pentax lenses if the continue to insist pricing them at the near-enough to the same levels as the more trendy brands.
Medium Tele-Zoom
70-200 f2.8 II EX HSM...........~$ 719 w/4yr warranty, no seal
60-250 SDM f/4....................~$1200 w/1yr warranty but sealed
Standard Zoom
24-60mm EX F2.8...........~$300 w/4yr warranty, no seal
DA* 16-50mm f/2.8........~$700 w/1yr warranty but sealed
Long-Zoom or Long Prime
100-300mm EX F4...........~$1100 w/4yr warranty not sealed
DA* 300mm SDM F4........~$1100ish w/1yr warranty but sealed
UWA Zoom
10-20mm EX f/4-5.6/........~$450 w/4yr warranty not sealed
DA 12-24mm f/4...............~$725 w/1yr warranty not sealed
Totals:
Sigma: ~$2569 (all with free shipping)
Pentax: ~$3725 (probably also free shipping)
So the difference is about what I expected at ~$1200...considering the warranty difference, I find the cost difference even more significant...probably add another $300-$500 for adding those extra 3-yrs to the Pentax warranty.
I just think this puts Pentax at a fairly significant disadvantage even with the sealed lens advantage. basically their larger price increases might shoot them in the foot because I wanted to buy all pentax gear, well almost all, and I cannot believe I am the only one. It is not that I do not want the pentax lenses, in fact I do, but needs must and well, saving between $1500-$2000 is significant.
Just my observations and why I am probably heading in a different direction than when I began...it has nothing to do with the lenses, but rather their price as well as the warranty thing. But who knows, tomorrow I might change my mind...hehehehe....
