Re: Aspect ratio frustration
I've found shipping within the UK from Jackson's to be very good - order before 3pm and it turns up the next day. So, it looks like they process promptly at least.
The only thing I would say is that the two boxes of canvasses I recently ordered weren't double-boxed or anything. The canvasses within each box had the outer two with the reverse side facing outwards, but no additional protection at the corners. They got to me just fine, but you might want to check with them for shipping internationally - I'm not sure the single box would be robust enough, and I'd like to think they'd be double boxed for that. The other parts of my order (thinners, brush washer) were very well packed - each bit individually wrapped in bubble wrap, and packed into a separate box.