GForce is incredibly dedicated to detail and you can get the original tapes (for M-Tron Pro) like the pretty amazingly sounding Streetly expansions. Quite something. As for VSM, they include all former expansions at the current (crazy) price of £33 until the end of April.
Thinking of getting this. Grown to about 10GB, I believe all extensions are included now. Already have RE-Strings for Reason but this is another cookie entirely.