I think you have to make up your own mind based on the information available and match a broker to your own requirements, not everyone's trading needs are the same.
You've also got to take into account the source of the information you read on forums like this, does it come from an active trader who has practical experience or does it come from a theorist who has probably never traded live (profitably) with any of these firms.
IB aren't perfect either, no broker is, they have their own problems.
There's another thread here on ET which discusses the same subject, again ad nauseum with some of the same contributors, you will see how some people were unable to substantiate their claims or support their argument when challenged with awkward questions. That kinda speaks for itself.
There's also an interesting article here which compares the pros and cons of ECN vs bucketshop.
You pays your money, you takes your choice
Good luck!
