Test drive xars are no different to otter production built cars.
normally they are allocated to individuals at the dealership to yse as company cars (tax break if used for test drives). They normally have various optional extras added as they are their Company cars, but the will be sold on as used cars, so not try are not specially designed as test vehicles he was telling you porkies.
If you are unhappy, speak to Volvo U.K.
I have heard the latest Volvo XC40 seats are not to the standard of previous Volvo offerings