Paired with rechargeable batteries and a battery charger (I prefer ones designed for USB charging), these lights can provide surprisingly good and portable illumination — perhaps not for reading, but enough for navigating otherwise dark spaces. They also can serve well in emergency situations, given how simple they are to operate.
Generally, I prefer portable lamps powered by easily removable and replaceable batteries. Investing in separate lower cost solar, battery, charger and light components (roughly $50-$60) rather than one integrated light allows for more versatility and easier troubleshooting.
Note, too, that as other components of inexpensive portable lamps break or wear out, the LED bulbs are often still salvageable. The financial savings with puck lights / push lamps are perhaps are not so obvious — except to folks who need lighting without wiring, those relying on small scale solar charging, and those who have sought out and been disappointed by more expensive portable lighting options.