Easy to install (pre-wired), composed of high-tech components (e.g. the integrated active/passive switch-volume pot is from MEC, same component like in any Warwick bass), german engineering.
There is no any difference between active and passive mode (meaning active mode is not discolouring the original passive tone in flat position of B/T/M pots). In active mode there is no output boosting (0db), hence no volume drop when switched back from active to passive. The electronics itself is dead quiet (no noise at all).
Very clear, very transparent sound. The REAL sound of your bass (and pickups) can be heard! So do not install it into a crappy bass 'cause you will hear the crap:-)
In active mode the Bass/Treble/Mid pots work well. Slightly cutting with mid pot, great slap tone can be dialed. Treble boost works also well and adds pleasent highs. Treble cutting is available in passive mode too. Good idea.
All in all: considering the price/value, features and quality (German made, I assume), this gear is worth the money!