Finally got a chance to experiment with Daler-Rowney cartridge paper A5 (5x7) (something that appears rare here in the States, but which I purchased from a NYS outfitter).

It is smooth, heavy, heavy weight and a pleasure to draw on. I was able to do two quick drawings with watercolour--and no buckling. The third piece, too much water, too many colours, didn't work.

So, I'll keep these pads for quick drawings in the house or on the road.