My experience as EK Plat: rarely have decent speeds, > 50% practically unusable for most of the flight. So have resigned to using it for simple e-mails... ...seems to be a known issue, as whenever I file for a refund, it is immediately issued without any query. Can't understand why they can't get it right, as on EY I rarely have the same kind of problems (although my last two flights were patchy as well there).