Got an alternative offer from Edinburgh for Cognitive Science too. And 4 x offers from others for Psychology BSc. I'm tempted to take the Edinburgh offer - although the course is not BPS accredited which I guess is the only draw back if you know you want to go on to qualify as a Psychologist, it would mean doing a conversion MSc.
Can I ask how long did it take to get the offer for the alternative course in UCAS? I've had the email from the Uni a couple of days ago but not got the actual offer in UCAS hub yet...