I have a Gibson Les Paul Standard Faded with 2 Burstbuckers Pro pickups. I'm very pleased with the tone of these pickups but I want to have the ability of coil splitting and the BBPro don't do that.
Have you thought about fitting a four conductor wire to the BBPros? If you like them and the missing coil split option is the only complaint then this would achieve what you want. Any pro shop should be able to perform the job correctly.
Any BKP you will choose will sound different - whether better or not that can only you decide. The Riff Raff, VHII, Black Dog and Emerald all have A5 magnets, so does the Rebel Yell. Mule and Abraxas have A4 magnets. Compared to the BBPro the Riff Raff may be brighter whereas the Black Dog may be middier.
But there should be at least one forum member here having replaced BBs or BBPros with BKPs.
Cheers Stephan