It buys you approximately two days (with reservation discount) of a single p5.48xlarge instance, which has 2TB of RAM, and 640GB of VRAM in 8x H100 cards. In fact that is the pricing example they use: https://aws.amazon.com/ec2/capacityblocks/pricing/

MI300X (RunPod) 192gb ram Hourly Rate: $2.49/hr. Break-even Point: You can rent for 2,410 hours (~100 days of non-stop-continuous use) before reaching the cost of the $6000 Mac. Mac's top out at 192GB not 2TB ;) Consideration: If your AI training requires sporadic use (e.g., a few hours daily or weekly), renting is significantly cheaper. MI300X will also get you result many times faster too, so you could probably multiply that 100 days!