I too have spent a lot of time in "the Box" and for me I hit the ball almost exactly the same in every shoe. The exception is the DryJoy Tour. For some reason I just can't get back to my left side when I wear them.
I don't swing nearly as hard as some of the guys here (ToddL, OUTIGER, Whaql1) but I am around 100-105 driver clubhead speed. I normally play in ICONs, but I have a few pair on Contours that get worn too. I have played in Contour Casuals and XPS-1s. I like the comfort of the XPS but the style is not my favorite. I have hit balls in both the M Project line, spiked and spikeless. I actually preferred the spikeless.
The biggeset difference I can say it that in The Box it is dry. I found the first time I used my Contour Casuals and it was a bit damp, they felt like they slipped a bit. Changed to a pair of ICONs and that went away.
Pick a shoe the first of all fits properly and is comfortable to walk in.It then becomes personal preference with the style, what gives you the best stability in all playing conditions.
As Todd says, If you lack a bit of consistancy in you swing the shoe isn't the cure, but it will help a bit.