Thanks to everyone for the excellent and useful responses!
I had never considered the FAs - largely because of the prices here in the UK. After all the positive comments, I started reading up on the FA77, but also the DA70. In the end, I went with the DA70, for a number of reasons:
- price difference... with current discounts, the DA70 cost me roughly half what the FA77 would have cost
- based on the comparison here on PentaxForums, and some other online A/B tests, I like the CA performance of the DA70, and the ever-so-slightly wider angle of view
- with my investment in the DA15, and no desire for / likelihood of moving to FF, I liked the idea of adding another DA Limited model to my camera bag
- did I mention the price difference?!?!
Time will tell if I get on with the specific focal length, but from what I've read on the DA70 in terms of performance, it should be a fun piece of kit.
I'd still like the 100 WR macro, and when I've sold my 18-270, 18-55 WR and 50-200 WR, I may well add that to my bag too
Then again, I loved ChristianRock's post that suggested I spend the money on a trip somewhere nice, so I can take some beautiful photos
Thanks again, all... This was entertaining and enlightening!