I am afraid you gave Infragistics the excuse to ignore your problem by simply mentioning Strataframe. Their support is not as helpful as here and you are not even guaranteed a response. But mentioning SF has simply given them an opt-out which they have taken.
Why don't you create a separate test form and create a dataset that duplicates what you are trying to do with the SF BO? This way you would simply be binding the grid directly to a pure .NET dataset and Strataframe would be removed from the equation. If you still get 6 or 7 seconds to load the grid then at least you know your problem is in the grid configuration itself.
Aaron
I will try this and I'll tell you what will happen.
We decided to use StrataFrame components because they are very pleasant to use.