If you plan to use the SSD for the OS/applications, you'll see a small improvement.
Apps load a little quicker... and Windows is a little snappier.
Where SSD *really* shines is disk-streaming sample libraries... where you're looking to achieve 500+ notes of polyphony.
Fast SATA-III SSDs are sustaining ~520MB/Sec on reads.
That's about 3 times the spead of the fastest conventional HDs.
As mentioned above, if you're using the SSD for the OS/apps, don't expect a 3x faster user experience.
That's not going to happen...