Smtp or API in Mailgun?

Question

Mail server

Site on Laravel. In RF. Russian audience. Instead of Yandex smtp, which considers site notifications to be spam, I'm implementing Mailgun.
I'm new, at this stage I plan to send simple notification emails. Perhaps in the future there will be mailings. Mailgun users share their experience. What to choose? What are the pitfalls, etc. How to smtp mailgun with tz spam blocking? Or immediately connect via api and not take a steam bath? It would be desirable to select at once with the minimum refactoring in the future.