WP7 IsolatedStorage Speed

I was wondering if it makes any sense fully implementing SQLite on IsolatedStorage as the "quality" of the db support will depend a lot on the speed of of the storage. I read on some posts that the speed of IsolatedStorage was a problem, but I've wanted to compare it with the speed of the Filestream. The problem is that you cannot compare the two directly so I had the idea to compare both of them with another "item" that is available on both systems. I've chosen a MemoryStream test as a constant. I am not making the same test between MemoryStream and IsolatedStorage or between MemoryStream and FileStream as I am not interested on how much faster is MemoryStream (that's why on the real device FileStream seems faster then MemoryStream but it's not true as it is not the same amount of data). I run the test for 10 times and then make an average (to have a more precise result)

Dividing IsolatedStorage/MemoryStreamSpeed=8.5991/1.2251=7.019 and FileStream/MemoryStream= 0.7/12.7=0.05511. To get an idea about the speed differences we devide the two results and we get 127.3634 which means that the IsolatedStorage is 127 times slower than FileStream. Of course this is not an exact result, but should reflect the speed difference. I might have some "glitches" in the tests but I cannot figure them out. If this result is at least near to the real one it doesn't make any sense to implement db engine on IsolatedStorage.

Another thing that I've noticed is that the x86 implementation of WP7 Emulator is much faster then the ARM emulation of 6.5 Emulator (at least MemoryStream implementation).

You can download the projects here