What do you like best?
It's so easy to learn and use. A wide range of customizations are possible. You can use canvas outside of a structured institutional registration system. And the cost is low or even free for educators.
In addition, there is a wealth of setup and usage information for administrators and users. Users/students are greeted with a popup to guide them in use.
What do you dislike?
I can't say I disliked anything about this, except for integrations. There are many apps available to integrate into Canvas, including Box and Dropbox, unfortunately without checking every single one you can't know if the addins are free or require a purchase/fee. Unfortunately the apps are not linked directly with Canvas, and you have to separately access their url.
Recommendations to others considering the product:
Do a feature comparison, along with pricing and ease of use.
What problems are you solving with the product? What benefits have you realized?
Several years ago we had issues with getting our adult students 'officially' registered in time for starting coursework in the official system. At that time I started investigating ways of providing course access to students in advance of registration. I found it much preferable to the institutional system so continued using it!
As an independent education consultant, I am using canvas for online course development.