Is it worth buying used RTX 3090?


Hi guys.
I have rtx 3060, which is quite basic, and lacks fast computation. It has 12 GB of RAM, which was a huge upgrade from my previous GTX 680 with mere 4 GB.
But now the market is flooded with used 3090 models. Probably they were used heavily for mining, but the price is so tempting. I could buy it for 700$ used, sell my 3060 for 300$, so it would be a 400$ upgrade.
Still, the risk of a burnt model is quite real. I’m not sure how durable those models are.
I purchased gtx 680 used, but it worked like a charm. I even resold it for 150$ after 9 years of use.
Would you risk, or would you save up for 4090? It’s around 1400$ pricier than 3090 in Ukraine.