I'm thinking of buying one if these things although have never seen one
other than in pictures. I presume you reckon it's OK then? Is it as
good as it looks in terms of ease of fitting; and how about stability in
comparison with a stone-resin job?

It seems pretty well made. It isn't in use yet, though. It is MUCH easier to
fit than a stone resin tray. To use the tiling upstands, you need to build
the alcove accurately and tile after fitting.

Christian.