Quote from EricP:
But, they don't really pay out "all profits" do they? They just keep a share of profits in a different way, in higher commissions.
Different firms will be better for different traders, no doubt. Traders that make consistently large average per share profits will benefit from "100% payouts" and larger commission rates, while traders that are high volume traders with smaller profit margins will often be better with firms with virtually no commissions charged and a profit split arrangement. Newbie traders that are net negative or breakeven will also benefit from minimal commissions and a profit split.
Ideally, a trader will work towards a broker that offers 100% payout and extremely low commissions, although deals like that are only available to very high volume, and consistently profitable traders.
Hard part is obviously everyone's deal is different, I can tell you I am with Echo and my commissions are a touch lower than the rates I have seen posted here for those other firms, and I get 100%. But as you also mentioned I am a high volume consistent guy, so I am sure a lot of guys have higher commissions than I do even here.
I can see your point that for a newbie to trading or a guy struggling, a % split is fine, but anyone with those firms who is consistently profitbale is making a mistake by not switching to get the same commish and a higher % or 100%.