Tires for E34 Biturbo

[quattro20v]

My Biturbo needs new tires, I've been looking around and don't see very many options because of the unusual size of the rears, 265-40-17. The fronts are very common, 235-45-17.

So far, I've been able to find these on the Tire Rack (prices for 4 tires):

Dunlop Direzza Sport Z1, W rating, 200AA, $698 USD
Michelin PS2, Y rating, 220AA, $888 USD
Bridgeston RE760, W rating, 340AA, $604 USD

And these from 1010 Tires:

Falken FK-452, Y rating, 300AA, $672 CAD
Continental Extreme Contact DW, W rating, 340AA, $850 CAD

I'm leaning towards the PS2's, mainly because I do not drive in the rain and tread wear is not an issue for me. Note that I have Sport Pilots on it right now, the ones prior to the PS2.

Does anyone have experience with these tires?