[northcoastgreg]

The problem with this "gap filler" is that you will never use one of these 3 lenses and I'm going to bet it will be your new 28mm.

That's actually not been my experience. I was facing a similar situation as the OP: I had a gap between 24mm and 35mm. Like most of the posters here, I thought it was no big deal: the gap was not big enough to really matter. But in practice I found myself sometimes finding 24mm to be too wide, and 35mm to be too narrow. I also had some 52mm filters that I wanted to use on something wider than a 50mm lens, so I picked up an old K 28/3.5. While I don't use the 28 as much as my 12-24, I use it a heck of a lot more than my A 35-105. I have found 28mm to be one of the sweet spots on APS-C for landscape photography, and I wouldn't want to be without it.

[eddie1960]

+1 on that greg, i find the 28 f3.5 one of my favourite lenses in general. the FOV is pretty much a perfect normal and works well for so many subjects. On 35mm i prefer a wider unit though (like a 21) since it is a different application
of all my lenses i think i'm torn between the fast 50 and the 28 for favourite length

[simonkit]

The 28mm is on hold for now - I'll see how it goes without it, I've just picked an FA 50mm F1.4 today though

Simon