We recently switched to Maileroo.. and its better in every respect.. better UX, product, delivery times, support, costs ... better.. everything
that is all
I love their simple and straightforward approach to SMTP. Their app is fast, adding a new domain and getting the configuration confirmed is also very quick, and their SMTP works perfectly. Now they are expanding into email marketing tools, and what I appreciate is that they are following the same principles in the development of this tool.