What do you like best?
The versatility is the best. From small, single-page blogs to e-shops to complex portals - Drupal can do it all. As an editor, I value how many options it gives me to present the content I want to share and if I have an authorization, the easiness of adding new options.
What do you dislike?
In most of the cases, it's not the platform for total beginners. You can make almost anything from Drupal, but with help of an experienced developer. But hey, we have found a solution! :)
And, as most of the open source solutions, you are responsible for updating your software. The company that develops the platform can make some amendments to make it safer, but It's your responsibility to install all of the patches.
Recommendations to others considering the product
There are a lot of comparisons on the Internet between different platforms. Of course, if an agency is better with Wordpress, it will say Wordpress is better. If their specialization is Joomla or Sitecore, those platforms would win. The truth is that there is no one, clear response which one is better - sorry! You have to evaluate the options on your own considering the strongest of your needs. Drupal, however, has a lot of "trial" options. You may want to build a demo of your product and see if it's ok. Also, there are many distribution versions that can help you with it, i.e. Droopler or Thunder
What business problems are you solving with the product? What benefits have you realized?
Most of our problems and problems of our business partners are solved with Drupal. We developed our own webpage od Rupal and it is our best advertisement. Instead of writing countless lines of code, e can build complex web pages like from Lego bricks - ready modules spare a lot of the time and prevent reinventing the wheel, again and again.