I am a heavy G Suite user. It is perhaps my favorite email account, with great Spam filtering, and custom domain name.
I pay roughly $5/mo as it came with my Squarespace account 1.
One of the things I like about it 2 is while you can use it in your favorite Mac app like Spark or Newton, where it shines is in the browser.
You can add extensions in Chrome to make it exceptional. This is what I have done, and where Streak CRM for Gmail comes in.
Take a look at this high-level overview of the functions