I have two. I would say they are all pros and no cons. I have one fitted in my Bitsa Precision that is my main gigging bass. MIJ body, Mighty Mite Jazz neck, Hipshot bridge, Wizard trad pup. Sounds superb played passively - great woody old school P bass tone. Click on the P Retro and suddenly the range of tones is expanded - like it was before but better, more articulate, greater depth, greater clarity. Difficult to explain empirically. P Bass on steroids. They are easy to fit, cause no damage to the guts so easily reversible, hold their value well secondhand. If the battery runs out you can flick back to passive. Easily and quickly recharged via the input jack. All good, really.