I prefer to purchase used. Reason being, and this is not extended to all makes, after a certain amount of kilometers possible problems should have begun to manifest themselves (if there are any). All cars are notorious for certain issues (electrical with VW/Mercedes/BMW, for example) and they traditionally follow the 'bell curve' as it is referred to in sales. The 'bell curve' is what dictates the amount of time companies extend warranties on their products to. If a particular products has an 'x' day warranty, it is because it has a failure rate of near zero up until day 'x'. After that date, the failure rate increases exponentially, plateaus at that exponentially raised level for sometime, and slowly begins to regress to the smaller failure rate. I.e., a bell curve. Point being, if you do enough research into when issues begin to manifest themselves in particular models, you can put in the work to find an immaculately cared for used vehicle, which should have already run the course of any inherent malfunctions. Plus, insurance and payments are cheaper.
I just purchased (as I mentioned earlier) an immaculate 1998 Mercedes E320 with less than 90k on it with impressions barely made in the leather. Full service records in hand I am pretty confident this should last me a few years.