I made a chat and embedded it on my website, the chat is really easy to use and allows me to customise pretty much everything I want.
Later on I purchased a plan and it was really easy to customise the chat using CSS, upload custom emoji's and use any of the other premium features the plan comes with.
There were a few things I wasn't sure how to do with CSS, and I contacted support and they helped write the CSS rules for me. The support is great and they reply really quickly.
I would highly recommend using this over other chats services which cost a lot more if you want a lot of users, and have less features.