shysal I bought and used testers for:
Hay Bale
Elderflower tea ( or something like that)
Crispy Crumble
Rope Swing
Plus at least 3 others that I can't remember the names of although "Trenchcoat" rings a bell.
I splodged carefully applied the testers to various parts of the room to take into account corners, the amount of light at different times of day etc.
We decided on Crispy Crumble, bought it, had it applied and now it is nothing like the colour I was expecting!
Daft thing is, the last time this room was done, I was looking for a sort of grey/green, but couldn't find the right colour, ended up using a soft pale green (Celtic Forest 4, had to get it mixed)
Now that I want a sort of taupe (beige) and have bought curtains to go with that colour, I seem to have ended up with the damn grey/green that I searched high and low for about 8 years ago!