I have one, and live near Salisbury. Happy to meet up for a chat and test fit in your garage! PM me if you are interested.
We had an S2 Roadster for 2 years, the Plus 8 since 2014.
Differences... the roadster is a traditional Morgan, with about as much power as any Morgan Trad needs. I consider the 3.7 roadster over powered.
The Aero +8 is essentially a modern car that looks like a traditional Morgan. It is quick, comfortable and an all day GT touring car. It isn't really a classic sports car.
The chassis is able to manage the power, the brakes also. I love it to bits. Ours had covered close to 40,000 miles and in the summer it is a daily drive. I have no intention at all of changing it, though I will try the new whatever it is going to be called.
I agree, the dash is horrid. Changing the dash is possible, but VERY expensive as most, if not all the cars have a drivers airbag in the steering wheel and a passenger airbag where the glove compartment would be. So specialist knowledge and equipment is needed to remove the bags. Once done you can fit what you like. I have the later steering wheel, whilst not perfect it is far better than the horrible thing on the early ones.
The big difference between the Aero Plus 8 and the S3 and S4 Aeros is the weight distribution: the Plus 8 has virtually no weight behind the rear axle line, whereas the Aeros have body work and boot, plus fuel. So the car is more like a front/mid engined car as almost all the weight is between the front and rear axles.
Another noticeable difference is the cabin width, there is a lot more arm/shoulder room as the Plus 8 doors are much thinner than the Aero doors with their wind up windows.