Honestly, unless you are super-critical and have OCD, I think you'd be happy with any one of those sets, be it a 900F, 940E, or R617. The differences among these sets are quite frankly not that big. Keep in mind that many people in this forum are enthusiasts that analyze this stuff to death and tend to magnify the differences.
A better question to ask is what will constitute most of your TV watching? Sports? Movies? Dark room mostly? Or mostly with the lights on?
My humble main system:
Vizio M75-E1; Oppo 203 universal UHD player; Denon 4300H AVR, Dual PSA S1801's; Monitor Audio Silver RX-6 mains, RX center, and RX surrounds; one pair NHT mini Atmos speakers; Home-built HTPC (Xeon E1230, 16gb RAM, Crucial M500 480gb SSD, GeForce 980Ti, Corsair CX600, CoolerMaster mini-ITX case); Roku Premiere+; Amazon 4K Fire TV