It makes sense comparing ViewSonic PX747-4K vs Optoma UHL55 because they both are able to give some premium features. Based on our rating, PX747-4K has a total rating of 7.3 out of 10 versus 9 for UHL55.
Advantages ViewSonic PX747-4K over Optoma UHL55
Bigger projection screen size: 60-200 inch vs 30-200 inch
Better brightness: 3500 vs 1500 lumens
Lower noise level, 27 dB vs 28 dB
Advantages Optoma UHL55 over ViewSonic PX747-4K
Lower power consumption, 170 W vs 310 W
3D support
Wireless connection enabled
Longer lamp life (normal mode): 20000 vs 4000 hours