Just in case any one needs a Observable Collection that deals with large data sets, and supports FULL EDITING...

Question

the VirtualizingObservableCollection does the following:
Implements the same interfaces and methods as ObservableCollection<T> so you can use it anywhere you’d use an ObservableCollection<T> – no need to change any of your existing controls.
Supports true multi-user read/write without resets (maximizing performance for large-scale concurrency scenarios).
Manages memory on its own so it never runs out of memory, no matter how large the data set is (especially important for mobile devices).
Natively works asynchronously – great for slow network connections and occasionally-connected models.
Works great out of the box, but is flexible and extendable enough to customize for your needs.
Has a data access performance curve so good it’s just as fast as the regular ObservableCollection – the cost of using it is negligible.
Works in any .NET project because it’s implemented in a Portable Code Library (PCL).
The latest package can be found on nugget. Install-Package VirtualizingObservableCollection. The source is on github. 

Answer 1

Good job, thank you for sharing
Best Regards,
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