I have two workers, a blue roan and a solid black.
They have lovely glossy coats with fine hair. I never use a brush on them as never found one that is any good for their coats
I have used a furminator but couldn't get on with it although it did remove lots of old undercoat.
At the moment I am using a wide tooth comb with an elastic band. I keep tension on the dog's skin and it removes LOTS of the old undercoat quite easily. I tend to do it in short sessions 10-15 minutes a few times a day.
I use a slicker when they have 'collected' things in their coats after a walk
but don't find it very effective otherwise.
I have a bag of things I have tried- various slickers, bristle brushes, nylon tooth brushes, zoom grooms furminator etc.
What works for one dog may not work for another
I am happy just using the comb and the rubber band as it works great on MY dogs and THEIR coats
( I have found that as they have got older, they are now two and half years, their coats have got longer and wavier
the blue roan coat is short and silkier than her sister's black heavier coat