G Suite’s Basic plan costs $6 per user, per month and gives users access to email via the Gmail browser tool, which includes email delegation, email recovery, spam protection, offline access, and attachment previews. G Suite also provides access to the business suite of Google Docs, works with third-party apps, includes 30GB of document storage and offers a guaranteed uptime of 99.9% with best-in-class security certifications.
One of the most important compatibility factors to consider with email is the mobility question. How often do your employees need to access email via mobile devices? That's an important issue because most email hosting providers deliver some kind of web client usable as a default inbox. Almost all of these can be accessed via a mobile device, so if your employees don't need to access their emails on the road that much, then such mediocre clients are probably fine.