Mine never misfired on stg 3 and 1.8bar 0.6mm gap, magnecore leads and MSD(not m developments) coil. I added a MSD (not m developments) 6al ignition amp when i went for more power whitch works great but has a downside of melting the dizzy cap quite fast resulting in misfires so now im tired of changing dizzys and gone for MSD( m developments) w-spark. When buying à aftermarket ECU u still need new leads, coilpack, loom etc so imo the w-spark isnt that expensive, u just need the chip and the rest you could do/get for your self but its nice to sometimes save the hazzle and time and go for bolt on bits.

Buying the old setup i had new was the same money really.