Reid,
I don't have sheep, but my initial thoughts is that a turf type grass is going to be just fine for the sheep.
As an example, the always-popular Kentucky Bluegrass is, contrary to the name, actually
native to Wales on the island of Britain. Bluegrass was imported to the then American colonies because it was great fodder for animals and it grew well in the region. In some ways, it grew too well and established itself so well that it is now endemic to North America. In essence, it is a weed. But as weeds go, it is one that I personally like.
Another popular lawn grass, tall fescue, is also native to Europe and was imported for similar reasons. And that foe to so many homeowners, crab grass and quack grass, they were also initially imported and utilized for forage.
So my thoughts are that the grass itself would be plenty fine for the animals. However, what I don't know is how well those grasses will stand up to traffic and constant browsing by the sheep. Perhaps areas could be isolated with fencing so as to give one area some rest time to grow back while the other is being utilized for
feed? Just a thought. But in the end, I am pretty certain that the grass itself will be good feed.
Eric