I recently built myself a fretless 5 from scratch (semi-scratch...hipshot hardware and someone elses pups), and put in Nordstrand j's with an Aguilar obp-3. I like the Aguilar and all: it's got a lot of control over the tone and has massive sound. I just keep finding myself switching over to passive and relying on the tone control and volume for my sound. Is it the pups? Is the the fretless aspect? Did I just get lucky? Or, am I nuts? This is a serious question, as I'm in the ordering stage for hardware and electronics for my next build, and am debating what to do. I'm just about sold on Aeros, and read in a previous post that they are designed to go passive (not sure if this is true, as I've yet to call and talk to the folks there)...should I forgo the pre?