The SPX8 doesn't even have better BEC - still 2S LiPo BEC. You have to connect the ESC to 2S voltage input by a sperate wire. That's something new, weird. Check out the manuals of the SPX8 and Vector8 at
www.lrp.cc
My CC BEC handles up to 10S, LRP SPX8 handles up to 2S for BEC and only 4S to power the motor. Whaz going on?
But the size and weight look nice. Also the different design of the Vector8 - high kv, 13mm diam rotor and 275g total weight (thats 100g less and even more)