Originally posted by Bui Because I saw a used K1ii at an unbeatable price, and also because I have decided that the K3iii is not what I want.
Similar story here, except my already having the FA 43mm and 77mm Ltds, along with some other very fine FF lenses, including the FA 35mm f/2 was a big push, because I missed what these lenses could do for me with film. I still can use them with film, but the K-1 II is obviously even better. As to the DFA 28-105mm, for me that was a no-brainer, as I got a good deal bought together in the pre-packaged kit. I reasoned that when mainly shooting FF, it would be a good idea to have a WR setup for it as well as for my APS-C equipment.
Since you also have a KP, I believe you will not find a huge difference in quality when using fine lenses. And this is a good thing. Each has its own virtues. if I am going to be doing a lot of trekking or biking around, I will be using an APS-C setup, especially the KP, beyond a doubt. But when just walking shorter distances, and not doing much beyond shorter telephoto, the K-1 II is great.
The DFA 28-105 is a great all-around versatile companion on the K-1 II and without adding very much weight. I've been enjoying my FA 43mm again as a versatile wide/normal walk-around prime lens, and the FA 35mm as a fast moderate wide angle, and with such compact, high-quality lenses you get a different perspective and aperture speed compared to what APS-C can bring, and these lighter lenses make the K-1 II much more manageable weight-wise.