It'll be a huge draw. When I was assessed in 2011, three out of the six in my group were from EZY. I met a girl who, on the day, had been trough the sim; she was from EZY. When I did my sim my partner was from..yeah, you guessed it. I'd say BA are pretty happy with ex easyjet guys. It is one of the biggest bus operators in Europe so numbers quantify.
I will also add that there were one or two in that group who believed they were BA pilots in waiting. Some folk still regard it as the be all and end all. You can't discard that factor, regardless of what is said here.