Points work fine but they do wear which changes timing, and they eventually wear out. But that takes a lot of miles and hours running. Proven simple technology. Getting good replacement points sets is not so easy though. So depending on miles ridden, a quick check and minor adjustment with a timing light, probably annually, is all that's needed.
The fact that they are almost entirely obsolete is due to economics and pollution regulations, not simply "EI is better". Electronic parts are dirt cheap in the quantities a manufacturer orders.
The mechanical points have several precision metal and insulating parts that have to be produced then the assembly has to be put together. Expensive processes.
Having electronic ignition controlled by an ECM allows the ignition timing to be continuously adjusted in conjunction with the fuel injection and VVT to get the cleanest burn possible, meeting tightening pollution regulations.
There's also the cost of maintenance, having a low TCO is important to the marketing team. An annual tune-up used to be expected, new cars seem to only need oil changes to stay running fine for years and years.
But remember we do not have new bikes with all the electronic bells and whistles, ours are inexorably aging from classic to antique. If you don't mind getting your hands dirty doing basic maintenance with wrenches and screwdrivers ... just stay with the points system. It doesn't take a lot of time or effort. (And if you don't like that dirty work, sell the old one and get a new bike with a warranty).
I have a Martek 440 EI on my 400, installed so many years ago I can't recall. Around 1980. I carried the OEM points set with me for a year or two "just in case" but never needed them. I don't put a lot of miles on now but the EI has never hiccuped, I check the timing every 2 years or so and it hasn't budged.
On the CB77 I put an EI unit I found through CB77.com (pretty much a dead site now) and it has also had zero problems.
The cons... many do use more power. Points are open for about half of a revolution. The easiest way (used by Dyna S and the Martek, probably others) is to have an optical or magnetic triggered electronic switch that opens the coil circuit when the trigger activates it. That is a very small fraction of a revolution though, so overall power load is higher. For the small fours (350 & 400) there is very very little excess power available from the alternator. If you also have a higher than stock wattage headlamp and don't do mostly highway riding your battery is likely never reaching full charge. I suggest using 5 Ohm coils - either stock or aftermarket - on the small fours. 3 Ohm coils will be too much load, and the "extra spark voltage" is part myth... and definitely not needed.
Some more expensive EI units have a dwell function independent from the trigger, and many offer various advance curves and have rev limiter functions.
Hondaman's ignition module uses your points as the trigger, and the dwell is set from the points so it's pretty much stock electrical draw (the electronics draw is miniscule). Without the spark erosion from directly switching a coil, the points contacts last essentially forever. The mechanical bits do need some attention, a bit of oil on the pivots and some grease on the cam. The springs and other mechanical parts don't last forever ... but almost. If something weird happens and the electronics fails, you can bypass the module and be back running directly on the points is a few minutes. Ideal for the belt plus suspenders gang.
