I am sure that there really is nothing in it in terms of safety, but the BA cabin crew generally do give a more professional impression that the VS crews, who tend to be younger and have a more 'chilled' attitude to life.

I think you might feel more comfortable (i.e. safer) with the rather less informal BA style. I know that I would, if I was of a nervous disposition.

And there really is absolutely nothing like the BA longhaul flight crew when it comes to the public address announcements .... They really sound so sleek and smooth that they come across as the Rolls Royce of the flying world's flight crews !