I'm not a fan of Zwartbles, personally. My reasons include :
- feet generally not great
- mothering not the best (for outdoor lambing, anyway)
- too friendly in a mixed flock - don't drive well!
- too much leg length - makes them difficult to turn
- not the greatest conformation
- fleece not very remarkable for spinning and so on
- not a British breed, and with upwards of 50 British breeds to choose from, why wouldn't you?
- Zwartbles here seem more susceptible to flystrike than primitive types
- higher incidence of mastitis in Zwartbles ewes than other breeds here
But they do have their plus points :
- very tame (is a plus and a minus!)
- very milky ewes, so lambs grow well - but ewes may need supplemental feed
- meat is fabulous, nearly as tasty as pure Shetland
Shetland and Cheviot are both fab breeds, in my eyes. Great fleece, lots of crafting applications. Lambs born without assistance, generally jump up and round the milk bar very quickly. However, Cheviot is slower-growing than Zwartbles, so you may get Zwartbles x Shetlands away sooner than Cheviot x Shetlands.
In the experience from here, all first cross Zwartbles lambs are black. Much harder to sell than white lambs, and black fleeces in the wool sack devalue the whole clip unless you are very rigorous at keeping black fibres out of the white.
I would think Cheviot x Shetland would sell better in both prime and store marts. And the ewe lambs might sell as breeders - we'd have been interested if still farming in Cumbria. (We investigated importing Cheviot x Shetland ewe lambs from Shetland, but they'd have never seen a tick, so we decided it was too risky.)
I'm sorry but I would eat the Zwartbles tups. They taste fab