>>> they have terrible staff policies and dubious staff vetting procedures
They have excellent staff policies whereby, just like most private hire companies, their drivers are all self-employed (or, at least, they would be if some lazy drivers, who wanted holiday pay, etc, hadn't obtained a bizarre court ruling preventing it).
All Uber drivers hold private hire licences and, as such, it's the responsibility of the relevant licensing authority to ensure that the driver is a a 'fit and proper person' to hold such a licence.
All of the information you require should be on the Uber website, Cleoval:
https://help.uber.com/riders/section/a-guide-to-uber?nodeId=5a9e5cd6-88f4-4597-b29a-4feb67d407c2
Private hire cars are usually significantly cheaper than taxis (especially in big cities) but you need to be aware that Uber set their prices by demand. So you could be quoted different prices for the same journey at different times of day.
All payments are made from your Uber account, and not in cash.
While Uber are doing a great job (which I heartily applaud) of forcing traditional black cab drivers off the road, there are other firms who're just as good, if not better, than Uber in many cities. For example, although Uber now operates in Sheffield, many travellers prefer to use City Taxis, which has more than 1400 drivers. They offer an app-based method of booking and making payments (similar to Uber's) but also accept both online and telephone bookings, together with cash payments.
So whether Uber is your best option might depend, to some extent, upon which city you're in.