I get 4 Zwartbles fleeces each year, from 4 wethers who live the life of riley
The fleeces are
huge!
It's easy to wash, doesn't felt, cards well and spins ok. A friend likes using it blended with trilobal to make knitted slippers.
All of which said, I wouldn't rush out to buy one. Being black or very dark grey you can't dye it really (I have done but it's a case of subtle dark tints
), it's too short to comb so must be carded, it's not particularly soft (though not harsh either) and not particularly crimpy therefore not particularly sproingy.
I gave a nice one to my local spinning group to sell for funds, suggested they ask £7 and it's still sat in their cupboard (and taking up quite a bit of space as so large!) Mind, it's unwashed and also has quite a bit of VM in it.
I shall have a go at peg-looming with some of what I have left, spun very very thick, I think, for a rug. Probably mixed with other fibres.