I had the pleasure of working with this group whilst conducting my masters dissertation over at Nottingham, really great people and I would definitely suggest getting in touch with Richard if you have questions.
As Clara's answer said, there have been some fantastic advancements in producing macroscopic BEC states with many atoms, but the proposal of Penrose  will require, as you said in your comments, something spatially separated and of the order of many atoms. What Richard and Ivette deduced in accordance with Penrose's ideas is that something more akin to macroscopic Schrodinger cat states  or N00N states  or the two-mode squeeze state  would be more appropriate, as these states are argued to have the quantum superposition that is important for Penrose's reduction interpretation. However, these kinds of states are proving very difficult to produce, even though there are suggestions as to how they can be produced . As far as I am aware, there have been no reports of a N00N state with even a few atoms produced, never mind the ~$10^9$ required to test these ideas. I think we are some way away to be able to test QG in this sense; although just how double-well BEC's  will play into this may be interesting.
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