SendGrid

La implementación en tecnologías como la son .net core y .net 4.5 es increíblemente amigable, no hay forma de que siguiendo el simple tutorial en la misma página web de sengrid puedas terminar confundido; simplemente agregas el nuget desde visual studio, agregas en tu código (o haces una clase genérica), las llaves necesarias que te proporcionan a través de tu perfil como más. Puedes agregar tu url y datos de empresa para evitar que tus correos terminen como spam en el correo de tus clientes.
Además, la forma en que se pueden editar las plantillas y sustituir ciertos bloques del contenido por texto o algún otro dato que generes en código es también muy sencillo y cómodo.

En ocasiones la IU de la interfaz de la edición de las plantillas para en estado “Legacy” es lenta, y en algunos casos el generador de plantillas (el nuevo) se cofunde un poco en el orden de los componentes según se arrastran a la pantalla, pero con un poco de practica se le agarra el chiste.

What I like most about Sendgrid is that most of the tools out there offer easy integration with Sendgrid. Some apps can even directly integrate with SendGrid without using automation software like Zapier.

Sendgrid's UI is a bit confusing and it took some time to get used to the options. The email editor lacks certain features.

Basic SMTP - no really a lot to like in fact it's awful

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SLOW support

It was very easy to integrate with my existing stack. SendGrid has really worked hard to make sure it's easy to use their software with other services out there. Most website builders by default ask you to integrate Sendgrid as your emailing service, and that was the case with my website builder. It was really easy for me to get started as all I had to do was add an API key in a provided input field. SendGrid did all the heavy lifting and I did not have to do any coding or even go through the API documentation(which by the way is very comprehensive ). You fill that that is the case in so many services that integrate with SendGrid, integration is light-work.

It is a little expensive, especially when sending a tonne of emails out and having a lot of contacts. Your email totals low-key add up when you have multiple drip campaigns and transactional emails set up. If you have a small budget it's really difficult to get measurable success on SendGrid as I found out when I just started while having a very low budget. The best way to get the best out of SendGrid is with a substantial budget, and that's a bummer when starting out.