My swing weight calculator software says D2.7, assuming a standard 51gram grip.

I've found the Golfsmith head weights to be to be very close to spec, so I would say right between D2 and D3. FWIW, I've built a lot of clubs and I can't tell the difference between D2 and D3 -- if you can then you are a better man than me.

As far as flex goes, I would expect them to play just a bit softer at +1/2" but again, I have never found that to be very noticeable with most people (myself included). Others with more experience with these shafts may have something more concrete to add.