Bill,
If you like driving your car with little worry, then eliminate the generator and voltage regulator and go with a 2-wire alternator.
There will always be those uncertain individuals that will have concerns with reliability of any new ... or old technology. However, when was the last time you had an alternator failure on your daily driver or family car? For me, I just broke a CV half shaft during a snow storm on my 1999 Acura TL with 200K but still have not touched the alternator and only replaced its fuel pump at 160K. I don't carry spare parts or tools (other then to change a tire) in my Acura or other family cars and no one drives concerned without them.
So, with an alternator, electronic ignition and TSV-modified SU fuel pump, why would I not feel as comfortable driving my Healey without extras as well? Steve suggests installing a Voltage gauge to be aware instantly if the alternator is not working. I don't have a voltmeter or amp meter installed in any of my cars and have been fine being notified by the charge light. Yes, it would help if when I had a failure on the road, I had a spare in the boot to fix the problem. However, would I have the correct component when the failure takes place, the proper tools for the replacement, and a safe location and the physical strength to do the job?
Bill, go for the components that provide greater reliability. The beauty is the installation can be reversed if you ever want to compete in a Concourse event.
Don't worry and just enjoy your Healey.
Ray(64BJ8P1)