All of them said they vastly prefer Lyft — they said Uber's policies for firing otherwise excellent drivers as soon as they dip below 4.6/5.0 stars makes them very worried.
As a user, I found the actual driving experience of Lyft better, but the Uber app is vastly superior to Lyft's – not being able to split rides being a major annoyance.
Actual implementation of policies can be completely different (imagine a ratings drop triggering an automated email saying "turn in your kit before 6pm today or a security detail will come get it" vs. triggering a non-confrontational call from someone trained to help you improve your ratings). Even the tone with which a policy is generally enforced (even if the end result is exactly the same) matters.
I don't have direct experience with either Lyft or Uber, but I wouldn't discredit drivers' impressions.
Having never used a ride-sharing service before, I hesistantly installed Lyft and handed over my payment information.
After the first ride, I didn't look back. I used their services maybe 10 times in 3 days in order to get around the city. Waits were never very long (we got rides at many different times of day, morning, mid-day, late night) and all of the drivers I had were friendly.
My experiences were all pleasant and the fares were reasonable. I can't speak to the quality of the Uber experience, but it seems many of the Lyft drivers were not too keen on the company.