Pros
The one-star reviews are understandably emotional and reactive. I give it 3 stars because it still has a ton of extremely knowledgeable and capable engineers, scientists, and technicians. There are a lot of great people here who make work more enjoyable. The company has a robust history as an industry leading liscensor of refining technology. It is not burning to the ground and will rebound as the oil market picks up.
Cons
However, it likely won't return to its former excellence. Misguided cost savings initiatives are damaging the quality of service, engineering, and likely R&D. Poor compensation, overworking employees, and lay-offs are degrading the depth of experience, especially as lots of older employees will be retiring along with their extensive experience. Field advisors are being put in charge of commissioning projects with very little experience because nobody sticks around long enough. Management only shows concern for the short-term profits for shareholders. Employees have been asked to shoulder all the burden of trying to meet absurd revenue targets, while overall the company has still been very profitable. It is a result of Honeywell trying to squeeze everything it can out of the company; when it stops being profitable UOP will likely be divested.