Currently, I'm working on a project. Its primary function is sending emails to an email of an agent, and users of this app can send multiple emails to one or more agents simultaneously. Can I use only SMTP directly in laravel for this case or use mailgun or SendGrid? I want to know the performance of using only SMTP for this case; I ask all these questions because I want to use a completely free method. Still, I like the best performance possible when sending multiple emails, which means I want all my emails to take only 2 seconds to 3. Please help me to find the best way!