Our team is very happy with our relationship for over 10 years now! The customer support has been great all along as well - they are always quick at responding, thorough in their advice/help / guidance etc., friendly & professional.
There's nothing I can think of that would make me dislike this system or feel like it could be better done elsewhere (aside from how much competition there currently seems to be out there). If we're looking into doing something new within an existing account then having someone who knows your business inside&out will help ensure things go smoothly. We've used them exclusively since 2015 when another vendor came onto market but was unable to provide what had become critical functionality required by us due to ongoing compatibility issues between products.