Same reasons you were thinking of: no points, so less to go wrong and they should be more reliable. They also provide a constant spark throughout the rev range and the Classic Alfa system is wrapped inside a normal distributor, so it looks original.
I had it fitted yesterday and it was a straight forward swap. The car seems to have lost some fluffiness that it had at low revs and it picks up better.
The selectable advance curves are for different engines and you choose the one (e.g. 2 litre) that matches your engine. You could play around and test others but, although the switch is on the outside, it's not very accessible and it's easiest to change setting with the distributor out.
Ian Ellis (
www.ianellisalfas.co.uk) did the spannerwork for me.
