i got my blues jr from a harp player. i absolutely love it!
for me, the bj is better for guitar. never tried the pj so cannot comment on it.
my bj was set up with 3 different preamp tubes (ecc81, ecc82, & ecc83 - all from jj) when i got it. i put the orig 12ax7's back in. i prefered the jj's. not as gainy & in your face as the 3 12ax7's but much warmer (a more lenny-like tone).
i just don't remember which tube was in which socket before.
oh well, i guess i'll just experiment & see what happens.