I would also agree with what other posters have said about BA PE. We have been lucky enough to fly Club which is superb imho. However, flying with 2 children now, this is just too much cash so we have since tried PE, but it's just not worth the extra money. I would sooner fly economy because it's just no different, and put the money saved to a Club class flight next year.
I am really surprised BA don't take the feedback on this seriously and change the way PE operates - even if it were to offer pre-bookable seats and dedicated check in - simple and cheap improvements. All you are getting for double your money is a smaller cabin (but share cabin staff with economy) and a bit more legroom. Good luck with your choice