Both monitors are very similar in appearance and have many characteristics in common, for example, the 27” screen diagonal, which is probably the most versatile diagonal now, both for work and games. They also use NES IPS panels that are VESA DisplayHDR 600 certified and support AMD FreeSync Premium Pro adaptive frequency technology, and the response time is set at 1 ms.
In addition, both monitors have a wide color coverage (98% DCI-P3), a maximum typical brightness of 450 cd/m², and a static contrast of 1000: 1. They are also factory calibrated (which is not typical for gaming models), so the color accuracy is specified at ΔE< 2 (for sRGB color space).
The main difference is in the resolution and the refresh rate of the screen. For 27M1F5800 it is 4K (3840×2160) and 144 Hz (via HDMI 2.1), and for 27M1F5500P – QHD (2560×1440) and 240 Hz. The new Philips Momentum will go on sale in June, with prices known only in the UK: £530 for the 27M1F5500P and £630 for the 27M1F5800.