Pretty sensible, but the main difference is that the different marques have a different look and approach to colour. The balance of the mix is different. The ergonomics of the kit is certainly different.

What isn't so different in the lab becomes quite different at the camera/human interface and that's where it becomes a matter of personal taste.

Looking at your lens list there are not many new DA lenses there. I think new lenses are generally better for digital cameras. Your K-x should not limit your photography, it's capable of very fine results. I would concentrate on the lenses.

Why must there be extra glass for the shutter? The shutter is placed between the elements of the lens usually, although I don't have the schematic in front of me as I write. I'm certain you will see no difference, there's nothing inferior about the leaf shutter lens.

Medium format lenses are the highest quality for professional use. All the Pentax 645 and 67 lenses will be exceptionally good.

The leaf shutter lens is for allowing flash synch at all speeds up to 1/500s. The leaf shutter is used with the focal plane shutter set to 1/8s or slower. It can be locked open so the FP shutter can be used when preferred.

What you really need though is a standard 75mm or 90mm lens. However, if the leaf shutter lens is almost as inexpensive then why not? Normally I'd expect it to cost quite a bit more.

We need to realise just how expensive colour was in those days. Even magazines in the 1950s found it very hard to afford colour separations. So much so that the same image would appear in several magazines all over Europe, presumably to share the cost.

The 1960s magazine Colour Photography is even then mostly in black and white.

Just a thought - generally I find 10 day listsings a bit off-putting as it is just too long to wait. 7 days seems more equitable.

Can't think of anything you've particularly missed!

It might be an idea to start by defining what your photographic interests are. The lenses you list are as diverse as it gets.

The matter is closed Tim, so we'll reluctantly have to lock the thread if we can't move on.

Do it in Photoshop John?

It should be possible to have contrary views and not come to blows over it, so please call it a day now and move on, both of you. I don't want to have to lock the thread, so let's get back to the original discussion, as a discussion not a shouting match.