I would guess how much use you would get out of it would be dependent on how you play, the context in which you play, and how your rig is set up.
On my S2, I quite often make small adjustments to the CVQ and Filter on the neck pickup. The way my rig is setup and the context in which I'm playing make these small changes very noticeable and valuable to me. So I would tend to recommend a 3-way switch over a 2-way switch since it expands your pallet of sonic choices. But that's just me; for others the 2-way switch does what they need.