If you have a large project, don't waste your time on smartresponder. Importing the database requires a lot of effort and takes at least two months. Customer support is unhelpful and makes mistakes themselves.
As for the service itself, the ideas for features are not bad, but the implementation leaves much to be desired. There are many glitches, redirects work inconsistently and slowly. Tracking of non-existent and undelivered emails is incorrect.
PS I will delete this review when the problem is resolved. If you're reading this, it means the guys are working slowly.