Played with 314-2, Z2, WD700, and OB2 over the last 2 - 3 years, will give you my impressions...
I'm a decent player - "A" level I guess, not quite shortstop level yet - very picky about my equipment. When I took up the game again a few years ago, I switched to a Z2 from my standard maple Schon shaft (still use the Schon butt). Very low deflection, decent hit, a little hollow feeling compared to a standard shaft, but something you get used to quickly. Once you go back to a standard shaft again, that feels really stiff by comparison.
I liked the shaft, could easily adjust for spin etc., but felt I was missing something. So I tried a 314-2, and went back and forth for quite a few months. The deflection is different enough between the two that I kept missing certain types of shots, didn't feel as comfortable with it. But because of the size it felt more solid, so kept trying.
Got a Mezz WD700, figured it was in between at 12.5mm and might work. I really liked it, a little more traditional feeling, stiff, comparable deflection to the 314-2. Played great, loved it - then the ferrule cracked. Took some effort to get it replaced but I did, and the replacement shaft was quite a bit heavier and played nothing like the one I had. Sold it. Still don't know what's more representative of the real WD700, I'm guessing they sent me a second or something as a replacement, or I just got unlucky and got one on the higher end of the weight scale (4.3 instead of the 3.8 I had). Threw off the whole balance of my cue.
So I went back to my 314-2, then saw Charlie Williams at a tournament and he was promoting OB, since he shifted his sponsorship to them. I tried the OB2, really liked it, even played a tournament with it right off the rack with a demo butt and demo OB2 shaft. Great playing shaft, wood ferrule was easy to get used to, only thing is with the dampening core it has a very soft hit, you'll either like it or not. If not, still have the choice of the Classic Pro, same size and basically same deflection, but with no dampening code and an actual ferrule.
Tips also make a different. The softer hitting shafts paired with a slightly harder tip can be a great combination, the opposite is true as well.
For now, I'm back to my 314-2, I realized that with some work I learned to adjust for spin just fine, I rarely miss a spin shot now, feel it gives me a nice solid hit with flexibility to do whatever else I want to do.
Definitely try the products out before buying, it's very much a feel thing, one person will say X is great while another hates it. I think Predator still has a decent warranty on their products, but I know OB has a lifetime warranty as long as the pad is left on the end of the ferrule. Can't beat that...
Scott