Eugene,

I noticed that the box for percentage slippage in the preference tab (equity slippage) is pre-set for .10, which is fine, and I understand why and impact.

Also noticed a 2nd box for 'slippage for market at close and stop orders (will adversely adjust entry and exit prices). If I am entering ONLY mkt orders a couple mins. after NYSE opens and selling at mkt whenever profit/loss alerts are triggered only, should I even bother to check that box? I am NOT using any mkt at close orders.

What's the diff between both slipage settings? Why have two? I am only using mkt orders w/ highly liquid equities.

Thanks,
Rob

The percentage slippage entry box only becomes active when you activate either one of slippage options (or them both) - 'Market/AtClose/Stop' and/or 'Limit' respectively. So there's no 'difference', they just can't live without each other.

You need to put there a number which provides a good approximation of real life slippage. It can be estimated with the help of your trading records.