[Douglas_of_Sweden]

FF preparations plan proceeds. Target number two is fixed and I've filled the gap between 20 and 28mm:

Primes:
SIGMA 20mm f1.8 EX Aspherical DG DF RF
SIGMA 24mm f2.8 ultra-wide II
SMC Pentax-FA 28mm f2.8 AL
SMC Pentax-FA 35mm f2 AL GC
SMC Pentax-FA 50mm f1.4
SMC Pentax-DFA 100mm f2.8 FREE macro 1:1
SMC Pentax-FA 135mm f2.8 IF
SIGMA EX 180mm f3.5 IF APO 1:1 macro
SIGMA AF Tele 400mm f5.6

Zoomes:
SMC Pentax-FA 28-70mm f4 AL
SMC Pentax-FA 28-105mm f4-5.6 Powerzoom

Converters:
Soligor AF 1.7x converter
Tamron BBAR MC7 AF 2x converter

The manual focus version of the 24mm ultrawide II has quite a good reputation and many users who claim they are better than Pentax manual 24mm's. The autofocus version seams to be very rare, but it is supposed to have a fast autofocus...and of course the same optics as the manual version. It of course comes less expensive used than the Sigma 24/1.8 new or used or the FA* 24/2 used.