When the K900 came to the U.S. it was offered only as a V8, and I bought one of the first ones (2015, VIP, V8). I now have 81,000+ carefree miles on it and get 26-28 mpg on a highway trip, on regular gas. I enjoy the extra power, especially when you need it at times. When the 6 cyl arrived a reviewer felt that it was under-powered for a 4,600 lb car. So, I am still a fan of the V8.