Echo is much cheaper than Bright. There are a lot of former Bright guys at Echo, mainly because of rates/software/blackbox access.
From what I have seen Bright is the best place for a newbie to go to because they have training and Echo does not. It is far better to pay a higher rate and have someone teach you how to trade than pay a lower rate with no guidance if you are new to the game.
But once a guy has it figured out and wants to take his trading to the next level they look around and seem to gravitate over to Echo. Echo does not really seem to even want newbies to the game, I have heard when people who have never traded before call in many times they tell them they should contact Bright and even give out the Bright vegas phone number.
For me now as an experienced high-volume trader I also am very glad Echo does not teach classes. There have been many credible rumors over the years that sometimes a trader figures out something really good and is with one of the firms that does teach classes, and a few months later the really cool thing he figured out is being taught in the classes after the firm saw him do it and the money dries up for him as a ton of guys jump on it. I know I have had some very good stuff running at Echo for many years and still have no competition on it (I would see it on time & sales if there were). That piece of mind would be worth paying more for to me but I also pay less, so a win/win for me.
Having said that though, Bright does have a lot of good things to offer, I would also tell any newbies that Bright is a great place to start. Both are very financially secure, very regulatory compliant (ie - no Tuco issues), and very straightforward about what you will get when you join. I would tell anyone that for me there are only two places I would consider, Bright or Echo. Bright if you need to learn how to trade, and Echo if you know how to trade.
It's my trading why you do you worry about what other people are doing?