>> They also mentioned 0 infections in fully vaccinated which is odd as other countries are seeing a number of infections in their vaccinated front line workers.

No, they had infections in the vaccinated. They had 0 infections in the previously infected, although another poster pointed out that the vaccinated (but never infected) group is much larger than the unvaccinated but previously exposed.

Frankly since the vaccine trains the immune system on the spike proteins I would think they're roughly equivalent and either both will offer similar duration of protection. If that turns out to be only a year I'm going for the vaccine next time, as the infection kinda sucked.

Immunity from infection does more than the spike protein, so it ought to be more robust against variants, even if one does show up that changes the spike protein enough to escape vaccines.

My understanding is that it's not clear at all with respect to variants, hence this study.

The spike protein has been picked for the reason that it's unlikely to change.

That was my thought as well. Natural immune response should have more vectors of attack since all of the virus proteins are available to make antibodies for.

As another comment mentioned though, the spike protein is unlikely to change much, and if it did, the virus would loose a major weapon in infecting people. So the vaccine is probably as effective as natural immunity in practice.