It's slow, unreliable, very feature-limited, and extremely expensive for what it is.
Especially these days, you could vibe-code something an order of magnitude better within a day or two and not be locked into a single author's rat's nest of code.
At this point, almost all new EmailEngine customers are AI startups. These are teams that know how to use LLMs well, which makes it interesting that they still opt for EmailEngine despite the extremely expensive $83/month price tag.
Especially these days, you could vibe-code something an order of magnitude better within a day or two and not be locked into a single author's rat's nest of code.