When comparing Opera Mail vs eM Client, the Slant community recommends Opera Mail for most people. In the question“What are the best e-mail clients for Windows?” Opera Mail is ranked 7th while eM Client is ranked 8th.
Ranked in these QuestionsQuestion Ranking
Pro Opera Mail CAN BE set as default email client in Windows 8 & 10
Pro Automagic smart filtering
After a bit of use Opera learns what e-mail belongs in what folder just by previous usage. This makes for a convenient way to have e-mails filtered without having to manually mange every e-mail.
Pro Free and based on Mozilla code
Opera Mail is completely free to download and use and it is based on Mozilla's code, which is what makes it a bit similar to Thunderbird in looks and function.
Pro Intuitive user interface
The design of the UI in Opera Mail is clean and intuitive, making for an easy to use client.
Pro Beautiful interface, customisable to your needs
Pro Calendar inclusive
Pro Chat included
eM Client includes integrated chat, so you don't need another application for chatting with your friends. All common chat services supported (Google chat, Jabber and others).
Pro Free and paid version
It is free for 2 accounts and as long as you don't use it commercially. Paid version comes with support and can handle more than 2 accounts.
Pro A perfect companion to your Gmail or other webmail you might have.
Pro Very fast
Con Sync is slow
Opera tends to be slower on e-mail sync when compared to other popular clients.
Con Muy lento al procesar varias cuentas de mail
Cuando se programan varias cuentas de mail se vuelve insufriblemente lento, al punto de tildarse el programa y tener que reiniciarlo. El sistema donde está instalado es bastante potente (Intel i5, MB Asus, 16 GB Ram) y aún así va muy lento. No ocurre lo mismo cuando está configurado con una sola cuenta de mail.
Con Poor integration with Yahoo Mail
Integrations with a Yahoo Mail account doesn't always work well in eM Client.