gzt: My F&P front load = Cold, 30, 40, 60, 90. For peace of mind I'll have to try a 'cold' wash and see if it's 20. Recently I've been running 40 instead of 60 and things seem ok.
Recently I've switched from Persil powder to Fab powder. The only difference I've noticed is Persil is more forgiving when you forget and leave the finished washing in the machine way way too long. I'm guessing Persil powder has some bacterial growth inhibitor that Fab lacks. As long as we don't forget, it seems good enough for clean work at least.
I haven't looked at the economics of liquid. I always remember it as contributing to unnecessary gunk everywhere, although it's been years since I gave it a good go.
Personally I always now use Ecostore powder and it washes as well for me in both top and front loaders. But always do a warm wash, 30 or 40

