PowerMTA is described as 'Email gateway application (SMTP server) that makes it easy for senders to adopt the latest authentication specifications ( SPF and DKIM) to comply with changing ISP policies for accountable outbound email delivery. No over hype. It just delivers' and is an app in the office & productivity category. There are 1 alternatives to PowerMTA for Self-Hosted. The best PowerMTA alternative is KumoMTA, which is both free and Open Source.
KumoMTA is the only true Open-Source PowerMTA alternative, capable of matching performance of several million messages per hour while providing granular traffic shaping configuration and automation across unlimited IPs.
