As long as the cut-off is fairly simple, I really think a BI (as you call it) is a good idea.
This is from a UK perspective, but my opinion on this is partly practical (to avoid waste) and partly ethical as the ruling classes generally don't view poor people as being worthy of financial autonomy (They actually have more in common with socialists on this matter that they would be comfortable with).
We've just seen recently a scandal where the government, rather than just giving people money ("Money can be exchanged for goods and services."), has paid some contractor to dole out - at potentially significant cost, although the figure seems to be wildly varying depending on whom you ask - some tins of beans and pasta.