What distributor do I go for? Electronic points of course and would prefer an Aldon, but anyone got any info on this and what is the difference between the A and A+ vac and non vac?

DISTRIBUTOR 123 ELECTRONIC IGNITION NON VAC PRE-A+
Price £164.26 exc vat
£193.01 inc vat
For: Classic Mini
Part No. C-27H7770
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Description
The all new 123 Electronic distributor is now available at Minispares. Featuring 16 ready programmed switchable advanced curves built in as standard, a must for any mini with a worn distributor. Full instructions are included with the system.For any A series, Pre A Plus engines without vac unit. Dwell is microprocessor controlled, depending on coil current. Works with any standard or High Energy coil with a minimum 1 ohm resistance. Direct replacement for the Lucas distributor.Replacement cap is GDC123 and rotor arm is GRA123