I was comparing with ChaosCloud: https://www.chaosgroup.com/cloud

For EC2, one would need to rent licenses for the V-Ray renderer plus V-Ray tends to be heavily CPU-cache- and memory-bound, so exactly the parts that get slow if you enable the Intel security fixes. Due to c5.9xlarge being Xeons, they are like 80% slower than a comparable AMD CPU.

BTW, calculator.s3.amazonaws.com quotes me $1119 per month for a single c5.9xlarge, so I'm not sure how you would reach $8/day when I see $37/day.

Then switch to the AMD based c5a.9xlarge which is even cheaper.

And you can reach $8/day using Spot or Reserved Instances. Not sure where you get $1119.