The customer service is great! They are always willing to answer any questions or concerns we have, whether it be about billing issues etc., they're very helpful!! Sometimes I wish that their system was more flexible for our needs but overall everything works well together as far back office goes (billing/sending emails). We've used them primarily because other companies were charging us too much money per month compared what most email marketing services charge so this helped solve some problems there - however now when using direct mailings from these solutions my budget gets reduced by 20% due mainly down time during send outs which can easily run over an hour sometimes depending upon volume at once.