IB, I believe, has accounts worldwide, but I don't trade internationally, so I couldn't say as to how good it is, but trading here in the US is fast, with instantaneous confirmation of trades. I think if you go to their site, you can view their traders' workstation demo. Many here use IB. It is also compatible with QuoteTracker for free intraday charting, etc.
TradeStation has the same commission structure, but charges for everything else, but if you want a really professional setup, it's well worth the money. They offer a self-contained professional platform for traders, including news, amazing charting capabilities, real-time scanning, automatic trading, back-testing, strategy testing, etc. Can't begin to say enough about it. If you're an active trader, you'll love it. My trading improved 200% when I went to TS. Wonderful fills, too.
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