More intuitive programming model than message-passing. Write-broadcast needs special hardware support that's not currently available, so paper uses invalidation. Statically chosen page ownership makes writes too expensive, so paper uses dynamic page ownership.
Centralized manager serializes page accesses.
Disadvantage is that centralized manager becomes a bottleneck. This is a partial win, but only because it moves a bit closer to a distributed solution. Disadvantage is that this distribution function must be the same for all applications and page usage patterns. Simple, but requires too many broadcasts. Still broadcasts for invalidation after write faults.