You're not going to know for definite whether it's B&S until you book, turn up and find out. IMO, there's nothing more annoying, and what you should do is walk every time!
With regard to nationality I'd bet my bottom dollar that most of these that recently have turned up in Swindon, Bristol etc are Romanian and to not put that on a profile is misleading. By leaving it blank would suggest that are you are British/English etc.
Personally, I won't go near a Romanian, 3 shit experiences! However I do realise that they're not all like that and I see that many punters on here will disagree! My opinion has been tainted and it is unlikely to change any time soon.
I always take a good look at the profile, if it is suggesting that the girl is British and she clearly isn't then it is likely that there are other lies as well. IMO, bottom line is if you smell a rat then give it a miss!