Just a matter of personal preference. I prefer cabin crew who are calm, professional and efficient. If they can add warmth and courtesy to the offering then so much the better.
The virgin crew I have experienced on a number of flights sem to be disorganised, disinterested and prioritising the perceived “relaxed atmosphere of the airline” over the need to provide a superior level of service to their premium customers.
My personal favourites are Asian crews (Thai/SQ) and some of the mixed nationality Middle Eastern crews. BA crews are usually professional and efficient but tend to lack warmth.