Hi Skirmish,
The Attack weighs a tad over 600g, which is about 1.35lbs. It's not as heavy as it looks, the original Randall Attack I have tips the scales at around 1.45lbs with its 400 grade steel.
I told Rob that the guard could be a weapon in its own right. On my template and specs I had it set to 8mm thick, I posted the template file here on the forum many months ago, but Rob had some 9.4mm thick 416 leftover from other work that he thought I might like better. So he installed it without telling me anything about it. It looked a little overly thick to me when I first saw it, then I realized why when I got the Verniers on it. I could have it reformed into a Randall Model 1 type guard which would reduce its exposed bulk considerably... but I won't.
You're right about the Brend Model numbers, it's my bad, not Rob's. It's an early Model 2, not a Model 1.