<p>I have a Grid in WPF. The Grid has a transparent background (necessary) and each of the cells potentially has a different colored solid background, or maybe no background. When I put arbitrary content in these cells, when two adjacent cells both have colored backgrounds (same or different color, it doesn't matter) there is often (and unpredictably) a thin transparent line separating them, allowing you to see through the grid at that line.</p>

<p>Does anyone know how this could possibly be fixed?</p>

<p>Edit: Meant to mention it in my question, but I've tried enabling SnapsToDevicePixels anywhere and everywhere I can, to no avail.</p>

My answer: Do a simple comparsion of the time taken to perform a simple Get/Edit/Update sequence.  I think you will find that LINQ to SQL is twice as quick.  I did a quick comparsion project when i was investigating the differences.
The results where:
Entity Framework 8,700 milliseconds 
LINQ to SQL 3,100 milliseconds 
Data-sets 2,000 milliseconds
So for me it was a simple question.  Use DataSets or use Linq-Sql - Entity Framework didn't even factor into it!
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