Need to replace 1 tire, can I mismatch pairs?

Today I had a blow out. My Bridgestone Potenza RE760 shredded. It was not worn out, but stuff happens. No drama BTW, just pulled over, totally controllable even at highway speeds. So, now I have 3 really fine Potenza RE-760s with about 1/2 the tread left. I could (A) buy 1 more same tire and have uneven wear (B) buy 2 new of the same size and have uneven wear ft vs rear (C) buy 2 new different model tires (like the hot new Michelins) or (D) buy 4 new tires. What do you think about running mismatched wear levels and or different models front & rear. My car has M5 staggered size wheels.

Oh yes, they fit in any position. I have 3 sets of wheels, 1 with snows, M5s with summer tires and a spare set because I got 'em cheap. I appreciate the advice. I am thinking the same. I don't like mixing brands either and since the rears wear out faster a new pair of rears is probably the way to go.

Update. I measured the tread depth, pretty shallow. I bought 1 matching tire, almost as cheap as the cheapest 275/35/18 at Tire Rack, and they will ship it tomorrow. I think that will get me into snow tire season and then I can consider what the best tire is for next summer.

With 2-3 months to go before throwing on the snows, probably not that big of a deal. For street driven tires, besides the obvious tread-depth consideration you've already measured (which, for spring/summer tires, goes towards hydroplaning resistance), the age of the tires should be considered, as tire tread compounds harden not only with use, but also age, even if they're not driven on much, or even just sitting. A substantial difference in age between the tires on the vehicle should be avoided, for the risk of handling issues. Sticking brand new tires on the front of a rear-wheel drive BMW but not the rears, possibly puts one at risk for something like an unexpected spin, if the rears were to lose traction before the fronts. Steven's suggestion to throw the older tires on the front axle would put you in the situation that if the older tires did lose traction, you'd be in a less-panic-inducing situation of understeer, compared to having the back end of the car unexpectedly stepping out sideways on you. Replaced the set of tires on my mom's car earlier this year when one tire was vandalized - she doesn't drive that much, plenty of tread depth remaining, but, besides the same tire being no longer available, the set was 8 years old; not worth the risk to continue running on 'em.

Sorry, Steven, but the better tires ALWAYS go on the back!

As a note in this thread, its best practice to replace tires in pairs, side to side.