Employment, the only measure of productivity that is considered in this context, was (maybe) modestly increased or otherwise not affected.

Given that it significantly improved mental health, it seems reasonable to expect that this UBI model would lead to some savings in public health expenditure. Arguably there should also be some savings compared to the administration of the current unemployment benefits that require the person to provide evidence of activity and other such things.

How well it compares in practice to the cash cost nobody knows as the experiments are all too short to really tell.