I am fortunate enough to travel business class with my job and when choosing a flight, I nearly always try to select an airline that only offers business and economy class such as Sabena, Delta, Austrian, Finnair, KLM and Air Canada.
This is because I believe that they offer a more attentive service to the business class passengers than those flights with first class. In my opinion, the business class product on these flights is often better than that to be found on a 3 class flight.

Does anyone else agree with the above?