Seems like a lot more hassle than using purelymail[0] for $10 a year, which has full Sieve and SpamAssassin and sub-addressing. 0. https://purelymail.com/pricing
Try the calculator at https://purelymail.com/advancedpricing and put in some large number of outbound email sends, like 2 million in a year, and the cost gets into the thousands.
Purelymail sent emails are $2.03/1000 plus $0.18/GB. Compare to SES, which is $0.10/1000 plus $0.12/GB.