The short answer
For a first touring trip, begin with soft bags you already own. Pack them, try them in the car and only buy replacements if the rehearsal reveals a problem. A fitted luggage set can be convenient, but it is worth paying for only when its fit is verified for your exact model and roof configuration.
Measure the space you actually use
A published boot capacity does not tell you whether a rigid suitcase will pass through the opening. Measure the narrowest usable opening, the floor width between obstructions and the height below the closed lid. Check the layout of your own NC rather than borrowing dimensions from an NA, NB or ND. Leave the original tools and emergency equipment in place while measuring.
A five-step fitting session
1. Photograph the empty boot. 2. Measure your existing bags when packed, including handles and wheels. 3. Put the heaviest bag low down and within the vehicle’s load limits. 4. Close the boot gently without forcing it. 5. Remove the overnight bag again: you should not have to unpack the entire car at a hotel. Keep anything needed urgently accessible.
Soft bags versus fitted sets
Soft holdalls offer flexibility, are useful away from the car and can adapt to awkward corners. They can also bulge beyond their listed dimensions. Fitted sets may organise the space neatly, but need explicit NC compatibility and a sensible returns policy. Rigid wheeled cases are convenient in hotels, but wheels and handles consume space and the case cannot reshape itself around the boot.
What to check before buying
Ask for external dimensions, not just litres. Check whether measurements include protruding handles. Look for sturdy zips, comfortable carry handles and a lining that is easy to wipe. A manufacturer’s “fits MX‑5” claim needs the generation and roof type specified. Do not treat a generic product photograph as evidence of fit.
A sensible first purchase
If your current luggage fails the fitting test, compare compact soft holdalls with modest structure and compression straps. A water-resistant bag is useful for carrying luggage through rain, but avoid assuming it is waterproof. Do not buy a luggage rack simply to rescue excessive packing: assess mounting, load limits, paint protection and security separately.
Before you leave
Repeat the fitting session with everything packed, not empty bags. Keep cabin items restrained and clear of controls. Leave a little room for groceries or a souvenir. The win is being able to load and unload calmly, not using every cubic centimetre.