I've used them both and I would go with the Mallory. I moved up to the MSD 6al-2, it's digital and I can't see paying the extra money for the MSD. I got a good deal on mine and I wanted to give it a try...buy the Mallory and your tach will work fine. Check out the Mallory HyFire 6, it doesn't cost much more and you get a TON more features, like start retard and 2 step rev limiter. Jegs has them for $259