Canson XL watercolour paper is an inexpensive 300gsm student grade watercolour paper. Is it good enough for watercolour? Let's see.
Even though it's labeled as coldpress, the texture is more like fine grain cartridge paper to me. It's not hotpress though because hotpress is much smoother. There's still texture on the surface but it's fine grain texture. Also, the paper is only textured on one side, so you can't use the other side for painting.
Fine grain textured paper is good for pen and ink work.
Here I tried wet on wet, trying to blend the colour into the white of the paper. The paint moves but movement is limited.
When I painted vertical lines into the wet wash, the strokes did not diffuse into the wet wash. With good cotton paper, the strokes should diffuse softly into the wet wash.
With this, I wet the paper and painted the colours on each side, tilted the paper to get the colours to mix. The colours did not move much even though the whole rectangle was wet.
For this, I painted the box with Gamboge, and painted red on the other side and tilted the paper to get the red to flow. Even so, it was difficult to get the red to flow.
This paper is not good for wet on wet techniques. It's difficult to get colours to blend into one another. If you want to charge in another colour to your wash, don't expect the colour to diffuse.
Best use of this paper is to paint fast. Get in and get out. It's good for use with pen and ink. The paper doesn't dull the colours so that's good. Performance of this paper is not very different from other non-cotton paper that I've used. You've to understand the limitations and work around them.
You may be able to find this on Jackson's Art Supplies (UK) too.