I am assuming you intend to use only one of those magnetic PUs, I would go for the Black Angel.
I am guessing you only want one jack socket on your guitar, so you will need to wire both pickups to a stereo jack so you can split the signals of each pickup at your preamp/mixer.
Then using a stereo cable you can plug each pickup output into a dual channel mixer/preamp to EQ and mix the sources. Ideally you want to be able to EQ the sources *separately*, the Black Angel and the JJB will need totally different EQ to get the best overall sound.
There are already numerous threads on dual channel preamps eg:
https://www.acousticguitarforum.com/...d.php?t=394253
People have their own preference, it really depends on your budget and what features you want (the individual channel EQ is the important one).
I use a Bose T1 (no longer made) to mix three PU sources, which is great and is actually more of a digital mixer with FX, easy to use. For a while dealers were selling them off cheap and a I grabbed a bargain., you can pick them up off Ebay.