Which dongle/dock should I get?

Just bought a new OLED steam deck and wanted to be able to connect it to my monitor

My monitor is 4k144Hz DP1.4 and HDMI 2.1

Most docks like this one or this one are HDMI 2.0 and say 4k60hz but this dongle says 4k120hz and allows an extra hdmi (i have another 1080p monitor)

am i missing something? the dongle seems like the better deal even if a majority of games wont run at 4k120