Which is better for a bright living room?

The TCL QM8L. Its Mini-LED backlight reaches far higher brightness and it has an anti-glare screen, so daylight washes out the picture less. The Samsung OLED looks better once the room is dark.

Which has better picture quality in a dark room?

The Samsung S90F. OLED turns pixels off individually, so blacks are true black with no blooming. The TCL gets bright and colorful but can show halos around bright objects on dark backgrounds.

Which is better for gaming?

The Samsung S90F edges it. Both run at 144Hz, but the Samsung has four HDMI 2.1 ports and reviewers report almost no input lag. The TCL is still a strong gaming set with four HDMI inputs.

Does the Samsung S90F support Dolby Vision?

No. It handles HDR10, HDR10+ and HLG. The TCL QM8L adds Dolby Vision, which matters if you stream a lot of Dolby Vision movies and shows.

Is the TCL QM8L worth stepping up to over the Samsung?

Step up to the TCL if brightness, Dolby Vision and anti-glare matter more to you than perfect blacks. Stay with the Samsung if you watch in dim light and want the best contrast.

Both should run for years. OLED pixels dim gradually with use, and static logos can leave marks over long periods. Mini-LED backlights avoid burn-in but have more complex dimming hardware. Neither has a clear durability edge.

Samsung S90F OLED TV vs TCL QM8L Mini LED QLED TV

Buy the Samsung S90F for dark-room movies and serious gaming. Its OLED panel gives per-pixel contrast, near-instant response and low input lag, and reviewers consistently praise color and clarity. Buy the TCL QM8L for a bright, sunny room or a big-screen feel. Its Mini-LED backlight with full-array local dimming pushes far higher brightness and adds Dolby Vision, which the Samsung lacks. The Samsung wins on black level and viewing angles; the TCL wins on brightness, glare handling and HDR format support.

Choose the Samsung S90F if you watch in a dim room, care most about deep blacks and wide viewing angles, and game on a console or PC that benefits from four HDMI 2.1 ports.
Choose the TCL QM8L if your room gets a lot of daylight, you want Dolby Vision and very high peak brightness, and you prefer Google TV with Gemini built in.

Prices

Samsung S90F OLED TV: $1,377.26 at Fireowls Corporation (last seen Nov 9)
TCL QM8L Mini LED QLED TV: $997.99 at Amazon (last seen Nov 9)
Difference: the TCL QM8L Mini LED QLED TV is $379.27 cheaper than the Samsung S90F OLED TV at the latest prices (Nov 9)

What reviewers say

	Samsung S90F OLED TV	TCL QM8L Mini LED QLED TV
Panel technology	OLED, self-lit pixels	Mini-LED QLED with full-array local dimming
Peak brightness	About 1,162 nits in HDR at 10% window	Up to 6,000 nits claimed by TCL
Contrast and black level	Per-pixel blacks, no blooming	Thousands of dimming zones, but halos possible around bright objects
HDR formats	HDR10, HDR10+, HLG; no Dolby Vision	Dolby Vision, HDR10+, HDR10, HLG
Glare handling	Glossy coating; reviewers call the panel coating poor	Anti-glare screen
Gaming	144Hz, four HDMI 2.1 ports, very low input lag	144Hz, four HDMI ports, Motion Rate 480
Smart platform	Tizen OS with Google Assistant and Alexa	Google TV with Google Assistant and Gemini
Audio	40W 2.1-channel built in	Bang & Olufsen tuning with Dolby Atmos and DTS:X

Spec	Samsung S90F OLED TV	TCL QM8L Mini LED QLED TV
Resolution	3,840 x 2,160p	3840 x 2160
Refresh rate	144Hz	144Hz
HDMI ports	4x HDMI 2.1	4 HDMI ports
High Definition	Yes	Yes
HDTV Format	4K	4K
Color	Black, Titan Black	Black
Screen Form	Flat	Flat
Display Type	OLED	LED
Assistant Support	Google Assistant, Amazon Alexa	Google Assistant, Siri
HDR	Yes	Yes
Connectivity	Bluetooth, Wi-Fi, RF, USB, HDMI, Ethernet, Opti…	Bluetooth, Wi-Fi, RF, USB, HDMI, Ethernet, Opti…
Weight	35.3 lb, 49.6 lb, 76.7 lb, 82.9 lb	89 lb

Spec	Samsung S90F OLED TV	TCL QM8L Mini LED QLED TV
Supported Streaming Services	Netflix, Disney+	Hulu, Netflix, Spotify, HBO, Disney+
Available sizes	42", 48", 55", 65", 77", 83"	—
HDR support	HDR10, HDR10+, HLG	—
Smart TV software	Tizen OS	—
ATSC 3.0 support	No	—
Processor	NQ4 AI Gen3 processor	—
Speaker output	40W 2.1-channel	—
SDR brightness (10%)	520 nits	—
HDR brightness (10%)	1,162 nits	—