I bought the Appsumo Amelia deal and have been ever so happy I did.
Why? Short listing of my experience:

- Easy to install, updated easily when updates are available.
- Handling events has never been so easy, including overview, scheduling, etc.

* Note for any European / Non English speaking users:

- Amelia has proven to be easy to use and translate (with other free plugin) 100% in your language of choice.
- Also one can link events and appointments to "products" in Woocommerce, so one can both book an event, maken an appointment, buy some products and pay for it at checkout in one go!
- The best? The best part for me is that due to the Woocommerce integration I can offer our local banking and palmet options, which is an example for any Saas solution nowadays.

Highly recommended!