I know this thread is super old but I thought I would give my opinion since I've been using the BBE Acoustimax for my bass for about 7 years. Bottom line, it fits me. I play a Carvin IC6P bass with the piezo pickup which has a very wide frequency range, super highs and super lows. This preamp really allows those to pass through nicely without distortion. This is one of the main selling points to me for this preamp. It's super clean. I can get a very flat frequency response if I want, boost the super low range or super high range by using the sonic maximizer settings or the usual low, med, high ranges. I don't use the notch settings at all as that is to help with acoustic guitar feedback.
Another nice thing is it has a all of the connections you need.
XLR out with gain attenuation and ground lift. - for sound to the mixer
1/4" out (muted by the mute switch) - good for output to an amp
1/4" out (not muted by the mute switch) - good for a tuner. I also use it to send to my headphone mixer so I can mute the live sound and still hear it myself to work on stuff without everybody else hearing.
Bottom line, it does everything I need to do, super clean, quality sound, no bells and whistles that I don't want.