It's easy for me as an individual developer or designer with limited technical knowledge (I'm not even sure if it has any) because there are so many features in this product! The customer support team at pilotmail have been very helpful when we've had questions about how best use their products - they're always quick enough respond but also understand our needs perfectly well without having us explain them over multiple conversations / meetings etc.. We really haven't found anything negative yet from using PMailer which makes sense considering its popularity within my organization; however like all software things can break down sometimes especially during upgrades where bugs may be introduced into your environment by mistake. Make certain everything works before upgrading otherwise downtime will occur until issues get resolved!!