SendGrid vs Twilio

Hey! We need an omnichannel inbox that's housed within Salesforce Sales Cloud that makes it super easy for our reps to respond to inbound communication (needs: clean inbox, provides historical context, etc.). We're a high-volume call center, and we get a ton of incoming SMS and email every day. We'd love a solution that lets us view all of that in one place — ideally Salesforce, as that's where our reps work, and we want to avoid needing them to switch between windows. Thanks!

Of course we chose Coresender to send our own transactional emails :) So I thought I'll let you know how we use it.

• We set up separate sending accounts for all company needs, eg. transactional emails, monitoring alerts, time to inbox. We even configured our office printers to send emails through Coresender.

• We have a real-time and extremely usable view into what emails go through each account, so each time anybody reports an email not arriving we're able to assist them in a few seconds

• We utilize our message timeline feature, so we can learn eg. if people are clicking on password reset links

• We always know how many of our onboarding emails are being opened which helps us improve them

• Finally, we have full controll over our suppressions lists, so we can add (and remove!) from them whenever necessary.

To sum up, at Coresender we're eating our own dogfood and it helps us stay connected to the product and understand our customers better.

For transactional emails, notifications, reminders, etc, I want to make it so writers/designers can set up the emails and maintain them, and then dynamically insert fields, that I then replace when actually sending the mail from code.

I think the ability to use a basic layout template across individual email templates would make things a lot easier (think header, footer, standard typography, etc).

What is best for this? Why would you prefer Mailgun, SendGrid, Mandrill or something else?