I don't think this topic is too emotional. You haven't followed discussions about chipping a car with some of the former board members.....
Seriously, the Bosch CDI units work fine for the task at hand and given their average age have shown an awesome reliability track record. Still, as they age some do fail. The good news is that they can be repaired. That is not true for some aftermarket units. Remember that even a 935 uses the very same principle of Bosch CDI ignition down to the same capacitor and switch. So it can't be too bad.
Aftermarket solutions (Permatune, MSD) were introduced with various marketing statements. They have been pitched as performance upgrades due to "hotter spark", "multi-spark" etc. I find these hard to believe and measurements haven't really substantiated these claims. If you have plug fouling issues you might as well address the root cause rather than using a multi-spark to mask and band-aid the problem.
On the flip-side reliability was less than stellar for some of the aftermarket units and many failed fairly early in their service life. MSD requires splicing into the factory harness and then there is the tachometer compatibility to watch out for.
With the MSD you do get the variable rev limiter that some find a nice feature. Many hot-rodders use MSD.
That being said I still don't see why one would rip into the stock harness to install an aftermarket ignition system if the stock Bosch system works fine. IMHO the benefits do not justify this. In the past when the Bosch unit failed and the only option was a 2600$ Bosch replacement it was a different story.
Ingo