We run a full MSD system on our VW drag car. Billet Dist, Blaster coil, plug wires, 6AL box, three step launch control and a retard box for the nitrous. It's been a great and trouble free system.
Here's a couple of things we found through actual use. We run the plug gaps wide, around .040" to .045" because of the strong spark. In fact, when we first started runing nitrous our tune up was "too lean" and we completely burnt the ground electrodes off of the plugs and the engine never even missed a beat at 7800 RPM with the strong spark. The distributor is easily tuned for advance curve.
You might need to install a "one way" diode in the alternator wiring to prevent engine run-on, its included in their kit and clearly explained in their instructions. By the way, they have all of their instructions and trouble sheets "on line" which is great for us late night racers.
In our race VW group, it is the opinion of everyone that their 6A and 6AL systems are bullet proof. But, everyone that has tried their "digital boxes" has had problems.
If you can afford it, I see no reason not to run the best.