The only thing I'd say ab out Boots is be prepared for the person behind the counter questioning what they're for. Boots don't agree with VLCDs and SOME branches can get a bit shirty.
I'm a diabetic so I just say they're for that (annoys me to have to explain and justify it though) so you can either say that if they ask or be ready to stand your corner. Alternatively, try a smaller chemist.
Like I said, it bugs me that they even ask ... they don't ask someone buying paracetamol whether they're for a hang-over - in which case they won't sell them as they don't condone excessive drinking. PAHHH!