Pros
Remote working commonplace across the organisation, considerable flexibility in locations and timezones. Pretty good undelrying infrastructure, VOIP services, hangouts, gmail, irc, travel booking service. Morale slightly better on engineering side of the organization, below average in design, terrible in sales and support. Pays fairly well, but has to in order to secure candidates in the first place. There are still some excellent people there, despite lots of good ones having left over the last few years, a trend which seems to be accellerating. However I've made some excellent friends for life. If you get one of the few good managers who shields you from the worst of the insanity, Canonical can be a mostly enjoyable place to work, however watch out if that manager moves on.
Cons
Where to start... Ineffectual senior and middle management, driven by a neurotic and in some cases borderline insane dictator of a founder, to the point of being abusive both in person, verbally and on calls/emails. Near to zero benifits apart from salary, pay for your own laptop (token bonus after 3 years service for refresh), no healthcare, bare basic pension, no stock options. Organization spends a lot of time and energy recruiting but not growing due to the almost continual revolving door of people exiting. Staff turnover is frightening. Up to 25% of the company hired within any given 3-4 month period. By my estimates at least a third of the organization is looking to leave or interviewing for external roles at any given time. Many are only kept there due to it being difficult to match Canonical salaries. No clear, cohesive strategy. The organization spins up in new directions as if it can't decide what to do, just as something begins to get traction it's often droped and some other hairbrained scheme is handed down from on high. Very few things are really developed to a finished, complete standard, leaving the organization and their customers with technology that rarely feels finished. Such an immense pressure on a tiny support team to patch up work that engineering should have been given the time and resources to bring to completion in the first place. From the inside the company just feels like the founders pet project, not a real company, and that's such a shame because it could be so much more.