The extension works and is very simple to set up - it simply does what it´s advertised to do, however, it provides very little flexibility, that is, to add your own messages to buyers or changing/correcting pre-defined text, a very important part of the sales process is the message customers receive from you.
CONS: Unfortunately, support is extremely bad! It took them a long time to get back to me and even when they did, they never tried helping, but simply defended the issue at hand - after several attempts to solve the issue I eventually just gave up with them.
The price is pretty steep for what you get. I would recommend looking elsewhere.