The visuals are amazing. Its easy to get the cloud resorce diagram.

It is very easy to describe complex architecture just by clicking and dragging things around. I like the premade components ready to use as well as the ability to add my own pieces of infrastructure to the chart.

Everything about it. Starting from design and able to select the compute power, storage, database, zones, etc. It is also very interesting to change the configuration on each line item, and accordingly see the price of your design. You can also change the 'Billing Option' to adjust how many servers/compute power you need in a day and in the end, you can see the final price/month for your entire data center.