Rule of thumb: mutually distrusting users sharing physical resources typically creates vulnerabilities. Do everything right and you still have covert channels. So long as they use physical separation rather than virtual then I'm excited to see this development. Separation that's (a) physically isolated per customer and (b) behind a stable interface allow the specifics of the security to constantly improve without work on the customer's end while blocking risks that come with virtualization.

See the co-founder in the comments. nebulon, would you clarify if it's physical and how do the boxes interface at the networking layer? That would be a start on upper-bounds of security.