It will be interesting to see how the experiment in Finland works out. Only unemployed people of working age have been chosen for the experiment and it pays approximately the same amount as unemployment benefit (so nowhere near £300pw). It will be interesting to see how the costs can be sustained five years down the line, when some of the unemployed will have found work but still keep their UBI. Housing benefit will still need to be paid.
We were told (hmm) that the original intention of Universal Credit in the UK was to stop the 'cliff edges' which happen when people move in and out of insecure work. UBI would also stop the cliff edges, because people would keep what they earn rather than being penalised for a few hours of temporary work.
I have long argued that JSA and ESA should be merged, while keeping PIP, which would mean that people not well enough to do a full-time job could do a few hours without losing all sorts of other benefits. Rather than a race to the bottom, I would want to see all unemployed people paid the ESA rate. I haven't done the sums, but I know many billions could be saved on assessments and 'courses', which could be paid instead directly to claimants. UBI could be part of that.
If UBI is introduced in the UK, I guess tax credits would stop, so some kind of transition arrangements would need to be made so that people don't lose out in the early years. Over a lifetime, 70% of people in the UK take more from the state than they pay, once family allowance/child benefit received as a child, state pension and any tax credits or other benefits are taken into account. The question really is whether this amount should be paid as a lifetime allowance, which would mean people would have to save for the hard times or paid out when needed, which involves the expense and hassle of means testing. JobCentre staff could even be retrained to do what they were originally supposed to do - help people find work.