For a secondary brokerage? Well, IB is actually my backup broker. My primary is TradeStation -- same basic commission structure, but for $200/mo, I get news, live charts, back-testing capabilities, scanning, ECN books, Level II, automatic trading, forex, etc. Seems very reliable but I've only been there a few months.
I think CyberTrader, Schwab, etc. might suit you if you prefer /trade comm. instead of /share.
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