I too have ordered a new (aero) Plus 8 in exchange for my Roadster. I've ordered the factory luggage rack for it - very similar to the rack now available on new +4s. In addition I've asked the factory to make me a secure case that can be bolted to the rack, one similar in finish to the Morgan luggage, but internally aluminium for security.
http://www.morgan-motor.co.uk/shop/products/PRO34382ae.jpg
I hope that as the new rack is much closer to the bodywork (no spare wheel) the luggage will sit close to the car and not obscure rear-vision.
Best,
Alan. (UK)

2012 Plus 8