The support is very responsive when you need help with an issue! I can't think about anything that we don't like at this point in time (and there are several things).
If it fits your needs then give them a try - they offer some great products for small businesses looking to keep their communications efficient while keeping costs low as well. Emailing invoices or receipts from clients has been greatly simplified by using our system which was previously done manually via email attachments saved locally until received/reviewed.