For ED, I sent the questions using its secure message box which is only accessible when you're logged into your ED account. The nice thing about this feature is that it allows you to ask questions specfic to your account. ING does not have this secure message box. You can only send an email to firstname.lastname@example.org. For account-specific questions, you have to call ING. So I made sure my question was not account specific.
At 8:30am this morning, I sent the same two questions to both ING and ED. I recieved a response in my email inbox from ING at 9:46am. The response did include answers to my questions. ED was also prompt in its reply. I received answers from them today. However, I can't determine the exact time. Messages received by ED's secure inbox do not have a time stamp. I can only say that the response came by 4:45pm.
So I'll have to call it a tie. Both responses were prompt and gave clear answers to my questions. One of the worries of online banking is not being able to get help. Although my experiment was a very small test, it's good to know they both exceeded my expectations.
Savings Rate Comparison
BTW, refer to this chart to see how the interest rates have compared over the last 9 months between ING Direct's Orange Savings Account and EmigrantDirect's American Dream account (I also include HSBC's OnlineSavings Account).