Which one? MSD AL6 or MSD AL6-2 for my stroker 418 (340)

Do you need the rev control? If you are 1/4 miling it a lot at the strip I'd consider it, especially with a 4 speed. Or if you can conceive of some current or future uses for it. $5 is not much. One possible downside is it's one more feature that could fail (KISS principle) in the future. If the Blaster 2 was getting it done why swap to the Blaster 3? The MSD is great because it gets rid of the ballast, but be prepared to go through caps and rotors quicker. That was my experience with an MSD 5 years ago on the street. Drilling vent holes in the cap helps to vent ionized air that tends to accelerate corrosion and deterioration of the cap contacts. Sounds like what you had with the Blaster 2 and whatever ECU/Dist combo was getting it done before. What makes you think the your previous set up had issues? Some gains in accuracy with a stock Distributor can be had by insuring the indexing/phasing of the rotor is correct in relation to everything else. Usually involves drilling holes a sacrificial cap so you can view the position of the rotor in relation to the plug wire terminal post when the distributor fires , checking it to see the rotor isn't too far away on either side of the post. Changing that involves custom reluctors with the roll pin slot drilled in different offset positions to allow changing that phasing.