Hi @CorruptBlu
We use our Google GSuite (what ever it is called these days) without any problem since March (except initially before we turned off digests) because we turn OFF all digests.
So, to answer you question, one downside of this service is that they have set usage limits and if you system overloads their system limits, they will block you (temporarily in the beginning).
My advice, for what little it is worth, is that if you are going to use Google for SMTP mail, you disable digests, or restrict digests to a vary narrow scope and range.
Hope this helps.