A customer, not an employee. I won't gush, see ting.com, it's an MVNO on the Sprint network.
EDIT: It kind of bothers me that someone downvoted this. It's not like I used an affiliate link or stand to benefit from this. Sorry for sharing :P
I would be remiss not to give them a huge amount of credit for their support staff. They really care about that. The only time I called in, a live person answered the phone after 1 or 2 rings and then proceeded to solve a somewhat technical problem without transferring me.
Anyway, I don't want to sound like a paid plug for them. But I like them a lot.
My experience with Ting as a customer has been excellent. Rates are great, flexible, and sensible. Customer service has been good. Flexibility with onboarding used and refurbished phones has been easy.
For about what I paid for voice and SMS on Verizon a year ago, we have two smartphones and a hotspot running both a person and some hardware across the country. My tightwad father's adopted the service (his first cell phone), and has since added another line.
T-mobile is starting to do the right things, but Ting already is.
Only reason I didn't sign up is Sprint has bad reception here. If I wanted bad reception, I would have stayed with T-mobile.