I'm late to the party, but I'll add a couple of comments.
I've got the DA 18-135, DFA 100 WR and both screw-driven and PLM versions of the 55-300, as well as a K-3, so I'm in a similar boat to you.
I think you've got a great deal getting both the DA 55-300 f4-5.8 WR and the DFA 100 WR. Having an all-WR walkaround kit with such wide coverage is perfect for travel, nature walks and general outdoor use.
For an occasional rather than regular telephoto user, the screw-driven 55-300 is more than adequate. There are even a couple of areas where it has small advantages over the PLM version: it's not prone to focus breathing and it's about 1/3 to 1/2 stop faster across the range. The image quality is very good - in fact I'd say it might even have slightly better resolution at 300mm than the PLM version. Here are sample images:
Pentax DA-L 55-300 f4-5.8 samples - Des(Australia) - Flickr Your version should be better because although optically identical it adds HD coatings - since I've now got two lenses with these coatings (DA 20-40 Ltd and DA 55-300 PLM) I'd say they make a significant difference.
My tip for using the 55-300: stop down one or two stops whenever possible. The resolution is significantly better, and more even across the frame.
Originally posted by Navmaxlp With the Macro, I doubt I'll really use it as as a short telephoto prime. It would mainly get used for it's macro purposes.
That's what I thought too when I got the DFA 100. But it's much more than that. As much as I like the 18-135 and the 55-300, I still often find it's worth swapping to the DFA 100 for its faster aperture and sensational resolution (sharp from f2.8 right through to f16). It's great for pets, flowers, landscapes, people, still life, birds and insects if you are close enough - all sorts of things. The 100 can provide "wow" shots more often than the zooms can. See samples here:
Pentax D FA 100mm f2.8 macro WR samples - Des(Australia) - Flickr