Thanks for the additional info & link Sorted !

+1 to all of the above (including the 'two of them' bit) !

Maybe something else to consider: if you intend to wait for the next Pentax camera then you have a long wait. They may be announced at Photokina (September) and then it'll be a few months before they hit the shops ... and at top price. So you are looking at a 6-9 month wait and paying the premium early adopters always pay (e.g. K5 was, if I remember correctly, around US$1,600 when announced and is now US$850).

You can't lose much on buying a K5 now and selling it again 9-12 months down the line if you wanted to.

The Porst is a different lens to the Cosina/Revuenon, but also has superb rendering. And this does seem very cheap for such a great lens ! You can find an excellent discussion on the differences between Cosina/Revuenon and the Porst on MFlenses.

Is that what they call the back-seat in a light aircraft nowadays

A quick look at the Chinese websites finds some lovely old-style leather camera holders (front detaches leaving the camera half encased in leather) with accompanying little matching cases (all slip on your belt) for the different lenses. Very nice.

What beautiful birds .. nice timing

That's an excellent lens if you are relatively close - used that a lot in the SOS Band thread (my flash was set to 1/16).

Love the Nikki and the Doves and the Spector shots !

If you are in a city the 31mm will in no way work for buildings. It will be great for landscapes (stitched or unstitched), street shooting, travel and portraits and would seem a good match for your criteria even though you are triplicating our FLs (sell one) !

I have and love the 15 Ltd. It is a lens like no other and is so small and light that it goes everywhere with me ! Absolutely stars errr shines err radiates at night work and in enclosed spaces.

Hi David .... the 150-500 is not the Bigma (that is the 50-500) it is called the Bigmos.

Coker - I'm not sure testing with a flash is the right way to prove anything. IMHO this lens should be much sharper than you have been displaying, outside and in real world decent lighting - not with a flash. Good luck with finding a solution. If you bought it from SRS why not contact Chris ? Maybe he can other a solution or offer advice.

f8 - f11 and ....... diffused flash !

That's how all the top macro shooters do it. Ambient light is just insufficient.