Depends what you mean by 'get along with'! Soays are sooo cheeky. We currently keep ours in with our Hebrideans. When we got this Soay trio last year, as tiny lambs, we introduced them to the Hebs quite carefully. For the first 100yds, it was the Hebs chasing the Soays, then the wee ones turned round and chased the Hebs for ten times as far, but all as a game. Now they are totally integrated.
having said that, we have in the past kept Soays with a number of different breeds as well as Hebs: Jacobs, Gotland, Shetlands, some downland types (which stoically ignored them!), even Manx, and they coexisted in relative peace.
Soay tups though are quite pugnacious, and will disrupt an otherwise settled group of other-breed tups.