It would be useful to support conversions between different types of Vector. The API and usage model is pretty straightforward for same-size types, e.g. Double and Int64, so I would suggest that we start by exposing that, and consider mixed-size converts as usage demands (we have had customer requests for at least the same-size convert). A possible instance method on Vector might look like this:
public Vector ToVectorDouble();
and it would throw arg exception for non-64-bit vectors (or, alternatively, it could be defined as an extension method on the static Vector class for only those instantiations that are supported).

I propose the following:

• Vector<Double> <=> Vector<Int64>
• Vector<Double> <=> Vector<UInt64>
• Vector<Single> <=> Vector<Int32>
• Vector<Single> <=> Vector<UInt32>