Another vote for the Aero 8, I would say this fits your requirement as a very capable long distance tourer for two. A boot (best on the S4) and a well sealing roof in my opinion makes it an ideal choice. Mind you it can be a bit of a hooligan too, if you feel so inclined.
I see Revolutions in Perth have both used Aero 8s and Plus Sixs listed for sale. If possible, drive a few different cars for each type and see what that tells you. Whatever you choose enjoy the moment.
