Pretty bunk deal for pennies IMO. A friend of mine tried tradeking for options I think, but he's closing it in favor of ThinkOrSwim (supposedly good execution and great tools, commission can get steep though--it's higher than Scottrade anyhow).
He did mention that to set up the automated-clearing-house deposit system with tradeking, you have to mail or fax them a copy of your driver's license + voided check. Plus their clearing time for ACH deposits was 5 days (it's 3 days for scottrade). As for their overall experience, he said Scottrade blew Tradeking away with regards to the charting and tools available (and real-time quoting).