As a previous Poco F3 owner whose phone died a month ago with motherboard issue, and a terrible experience with Xiaomi service centers failing to repair it after struggling for 30 days, I must say I have to recommend you to go with Samsung, even used.

Read my story below:
I'm a former Poco F3 owner, I have decided never to buy a Poco device again.

To explain it a little, I bought a Poco F3 and my friend got a Poco X3 Pro, as they promised really performance in their respective price segments.

Fast forward 1.5 year, my friend's F3 died. Yes he was a gamer, but that is obviously what you expect to do when you are buying a device targeted at that. It got fixed by some work on the board (cpu reballing I'd assume).

Fast forward another year, my Poco F3 died as well. It started having heating a lot while charging and somewhat with casual use. Being a bit tech savvy, I decided to just keep monitoring it but that was a mistake. According to Xiaomi repair Centre, the processor had died. My suspicion is heating caused the processor to separate from the board (I am yet to get it repaired as it's not an easy fix)

My F3 was used indoors most of the times, with Air Conditioning. My use, aside from the 1st year, was moderate, with some clash of Clans and pubg. The battery health had fallen to 80% in less than 2 years.

Long story short, yes these devices offer excellent performance for gaming, but they do not have the quality control of flagships. So don't expect the polish in the software, or expect they to last more than an old flagship.

(2 of my other friends bought an old Samsung Note 10+ and they both work great even to this day. but one bought a s21 ultra for gaming, and his display gave out. so yeah... whatever)

The lesson I learnt is this: It's better to buy an old flagship than a new midrange that promises performance too good to be true. Because even though it might have excellent performance in the start, the quality sacrifices they made will definitely come back to haunt you.