Interesting link - thanks, but I've order my screws now. Quality TIMCo ones at a third of the price of those.

The prospect of removing 2,000 washers by hand was a daunting one. Let's say 5 seconds (a wild guess but probably quite optimistic) per washer and that adds up to 2.77 hours of toil - without taking into account the occasional 'difficult' one and then there is the inherent danger from the odd sharp edge... still, it would be good for the soul perhaps.

Nail guns are way too heavy and unwieldy or, as mentioned, they come with a cumbersome trailing airline. Either way they are very difficult to use and especially to use accurately IMHO. They are also highly dangerous. Only last year my brother-in-law nailed his hand to a piece of 2 x 4 with one.

So overall, yes, I would far rather drive 2,000 screws with an electric screwdriver than 2,000 nails - whether by hand or by gun.

The benifits AFAIAC are:

much quieter
much safer
much less tiring
much more accurate**
much less likely to split the timber

[** A screw is much easier to place and drive accurately with a relatively lightweight cordless impact driver than pretty well any other tool on the planet IMV. plus it can be undone and repositioned with ease should something move whilst you are making the initial fix.]

I've been driving screws by hand, with Yankee drivers (yes, I am that ancient), and with mains & battery drills, & cordless impact drivers for over 40 years now. I know what I'm doing with them and I've always preferred them to nails. Hence why I placed so much store in finding a screw-based solution to the problem of fixing my bracketry.

Thanks to all for their suggestions in this thread. It's been useful.

Darn it, missed the party!
Bit perplexed why your SE doesn't consider ply and OSB carried down to the sole plate and nailed through as sufficient reinforcement of say, skew nailed studs, as per Ringi.

We would normally run a sole plate around the strip found and then separately fabricate a frame section, nailing through (Paslode 90mm annular ring) headers and footers. This assembly is then placed on top of the sole plate, forming a double footer, held together by skew nailed 90's and OSB overlapping both footers. Cold bridge not a grave concern in an outbuilding...

Have I missed the sole plate fixing detail? If your SE is this worried about uplift, it must be quite something.

Beau's Turbocoaches are great and those 40mm bad boys go through the large hole a treat. Sorry about your nail allergy; have you checked your SE's roofing drawings for joist hangers?!

Interesting link, yes, I was aware of that, but this was not actually the screw under consideration at the time.

Things have moved on however and I have ordered a suitable TIMCo screw at considerably less than that price.

"Cold bridge not a grave concern in an outbuilding..."

Ah, but this is not 'yer mother's average outbuilding. It is being built to Passivhaus standards starting with 300mm of IsoLohr insulation care of the lads at CRS Future Build who are advising on and assisting with the slab.