Great move. Will probably switch to it immediately from Sendgrid as soon as it goes GA. Sendgrid recently killed their free tier (100 emails per day) and their lowest plan is now $20/month for 50,000 emails. It's totally overkill for low traffic projects.
Even with those pricing structures, 95%[1] of the spam I get comes from sendgrid. To their credit, their abuse@ address is good at handling the reports and they reply with a followup that the report was received and able to be acted upon[2].
The volume of spam (for me) doesn't seem to be decreasing from them, so there's a lot of moles to whack.
[1] Just a guess from looking at the last weeks [2] I know it's automated, but often there's 2 that come with the 2nd one stating it's acted upon, so i'm hopeful.