I've ran some of the DUI units in my cars, they work great and are far more durable then a lot of the MSD stuff I tried. Probably not the ultimate in performance ignition systems, but plenty good enough for street use.... As far as the $300 distributor, probably more then you need in the sub. One of the good HEI aftermarket distributors would be fine, or maybe even just installing the HEI coil and cap unit that Accel sells would probably work excellent. Hotter spark should fire the mixture better, maybe a minimal increase in mileage....

BTW, the DUI units are a high quality build. They look great when checked on a scope or tuning the distributor on a distributor machine. Might not have the big name like MSD, but they also don't have a lot of the failures like the MSD boxes have.... Take a look at the pro cars, NASCAR, NHRA, road racing or whatever. They all run a dual system so when system 1 fails you can switch to system 2. Says a lot right there about the reliability issue......