I believe the 740 and 750 both have same motor, so probably could turn up 740. Having had tracks and seeing how they can absolutely save a crop when the weather turns nasty wet, I would not be without them. Having said that there is still lots of combines on duals being made, and most years it would be fine. Combine is definitely easier to service with tracks(not counting track maintenance).
I would say the year makes as big of a difference though, lots of very nice improvements in 2016, prior upgrades would be dynamic cooling in 2014 I believe it was. 780 got those improvements one year prior.
In tough wheat with heavy straw or tough soybeans power can be an issue. I have a sense that you grow good heavy crops, so can't discount the need for power.
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