I think i might be the only user on the boards still using it actively, so I think I should shed some light on it.
If you've played with either the mid or midplus version of the tour, you already know the racquet is a spin machine. What happens when you elongate the strings and open up the pattern a little? Massive spin. Probably the best spin potential of any racquet currently available; it has an open pattern, o ports, it's extended, and it's pretty flexible.
Feel has never been an issue for me with the racquet, even using full poly, because it cups the ball so much, although I will warn you, it is a very dampened feel. The OS does not have hard grommets at the throat, and you'll probably feel it.
The power level feels like a typical player's oversize with just a little more pop. It isn't going to do all the work, but it will certainly get the ball deep in the court with decent strokes.
As for serves, the massive spin potential carries over. It isn't a huge serving racquet, but some of the kickers you get are unbelievable, and everything, even flat serves, seems to come off the stringbed with a ton of spin.
Volleys feel sweet and are easy to keep deep. I get some extra court penetration, from the spin potential, with the extra slice on the ball. Touch shots are a little tricky to get down with the racquet simply because it's an extended OS with oports, but it's only because it isn't like any other racquet, so you just aren't used to it when you first try it.
I would say the racquet is strongest from the baseline. The spin potential jumps right out at you when you first hit groundstrokes. But, the best aspect of the racquet, which is almost always ignored in most racquet reviews, is the frame's forgiveness. I swear sometimes that the whole racquet is a sweetspot; it seems even when I manage to frame a ball, it still feels sweet! I can keep the ball deep in the court almost effortlessly because of this.
Other people will probably disagree with me when I say that the racquet is control-oriented, but that's because they have somehow come to the conclusion that less power equals more control, which I disagree with strongly. If you can handle a player's stick with some extra pop and spin, you'll love the tour OS.