I've done the one in Oxford and also one with CTC Aviation in Southampton.
They are both high quality courses. The sim time in the Oxford course is done in a full flight EFIS 737 sim and the CTC course is done in either their 737-300 or 737-700 fixed base sim.
As regards quality of groundschool and sim instruction I would put CTC ahead of Oxford. The groundschool in CTC was much more interactive and more was covered in the way of CRM. This is not to say that the quality of Oxford's was in any way poor - quite the contrary, it was very high.
I'm not sure of the cost of both courses.