Hire before you Buy?

As I have previously mentioned we are seriously thinking about changing from a caravan to a motorhome. Even went as far as visiting a dealer today to discuss the nitty gritty. Our sons are rather keen for us to hire  a motorhome before we finally decide but I have mixed views on this as I think I am capable of reaching a decision without doing that. The model we are thinking of buying is very similar in layout and size to our current caravan. In order to reclaim the hire fee we clearly have to hire from the company where we buy the motorhome. They only have a relatively small basic motorhome for hire so I am not convinced it would be a real test nor would going away only for a few days when in the main we go away for two months. What do people think?

David