I think it could work and be similar to when Robbie Fowler returned to Liverpool. Despite being well past his prime, he still made some worthwhile contributions as a squad player. Could be valuable backup to Ulloa as he's capable of playing the same role.
I actually met Bobby recently and he is fully fit and available for loan. He thought the loan terms being offered were reasonable but he's had no offers at all.
This was nearly 2 weeks back so I would imagine QPR's decline will decrease the number of Championship clubs they are prepared to...