hi Simon!
you're bang on the money with the roof observation - the S1 has indeed had at LEAST 3 different roof styles created for it.
the original roof, (the one still on my car) will (with careful usef of magic) stow very neatly foldded in on itself - creating a completely flat rear deck behind the seats. Even with no tonneau it looks neat.
This roff, despite being cosmetically great, is less than practical to put up and ddown, requiring a couple of minutes fiddling.
Additionally, it doesn't necessarily fit very snugly - and can leak, it can be more or less hassle dependding on the individdual car and the exact fit of the hood.
Dealers offered owners a free upgrade to the Mk II hood where requested. This is a concertina hood that stacks ont eh rear deck.
Issues with this hood were also prevalent it seems that lead to the Mk II hood being made available - which is the style seen on the SII I believe, then an evolution of this (I guess?) for the S3.
The general nature of S1's means that they are pretty bespoke items - I've seen various door layouts with and without window switches, and various trims. Thats part of the fun of owning an Aero though - the individual nature of it as a one off creation of the Malvern Factory
In terms of S1 / S3 - the S3 is certainly more livable day to day and has the power, the sound, and the overall togetherness that makes the car the serious proposition it should be for Aston / Ferrari buyers.
The S1 was never realistically competing in that market - it was up against the TVR Tamora and the Marcos. The Morgan is better put together than either, but doesn't have the consistent finish that the S3 has. On the other hand the stripped out racer for the road feeling, low loud and unfitered makes it an electric proposition for a weekend car
