Uber has several problems that make it a poor experience for consumers IMHO based on my own experiences:
1) Their drivers are not well-trained or carefully selected. As a result, some drivers don't know where they are going and are just bad drivers who would never be hired by a taxi company (which in my book is pretty bad). So your trip could take twice as long as it should, which means if you're late it's very hard to depend on Uber.
2) It costs a lot. Some fares depending on how slow your driver is could be twice as much as normal cab. They also use "surge pricing" which can increase the price of your fare.
3) Uber customer service has a bad attitude. Sort of like "you're wrong, this is why we're right". I'm not saying their customer service is worse than cab companies, but I am saying my experience with Uber customer service was poor.
So in summation, Uber is a good idea, poorly executed. I'd try one of the other cab hailing apps in your city (Flywheel, Instacab, etc.) because you're likely to save money and have a better driver.