Explorer, which moto, LPG?

Good evening, I came to the Explorer after a long search, but I still have an XC90 on the list. Since I know about the model so far zero, which engine is best suited to the model? Online there are some 2.3 engines or should you rather grab the 3.6 engine right away? I hope for a few experiences from you, also problems or disadvantages of the model, whether plug in or not I am still unsure and whether an LPG gas system is worth it.