They are very responsive about changes we make after initial release or any new features added during our support contract term! I like how they use their own tools for development (not relying only by open source), which gives them more control over quality & stability than other vendors who do not have such system set up themselves(like us).
Their customer service has been great so far - always willing / able answer questions promptly via email as well if phone calls weren’t possible at time due day light savings etc.. It would be nice though it was easier when you could talk directly without waiting days sometimes between emails sent back'n forth trying get through your contact person there but once i did speak wih my rep everything went smoothly from end user standpoint no issues encountered yet.