I'd like to reuse one allocated buffer to read and one buffer to write to the mongodb. Currently one must use WriteBytes(byte[]) and byte[] ReadBytes() to read and write byte arrays. These arrays must be pre allocated with the correct size.

If you want to reuse a buffer it would be nice to get some overloads with a size restriction like:

void IBsonWriter.WriteBytes(byte[] bytes, int size);

This overload should only write size bytes to the document.

void IBsonWriter.ReadBytes(byte[] buffer, int offset, int size);

This overload should only fill the count of bytes defined by size starting at offset. 

This would reduce memory fragmentation in the program.