Overclocking is risky - if you're doing large batches you may find how much you can overclock it by varies with batch, and don't forget the overclocking can stop things working at other temperatures.
As for me i'm waiting for st to bring something out thats meant to run that fast.
You can ''overclock'' it and try. But no guaranties. I've done it and my sample ticked at 108 MHz. I posted this info in one of the SPI topics with hardware NSS.