Plug one of those Anker cigarette lighter USB adapters into lighter socket, put a load on it, and tune through the 2m amateur radio band to see if there's any noise. That's the problem I have with a fairly expensive adapter I bought a few years ago.
As a follow-up, I bought an Anker PowerDrive III 2-port 36 watt car charger. It seems to be well made. So far, I've not detected that it's generating an RFI in the 2m amateur radio band. The springs behind the negative terminals on the side of the charger must be very stiff (a good thing) because it's difficult to insert in the lighter socket on my Ford Expedition (not a good thing).
As a follow-up, I bought an Anker PowerDrive III 2-port 36 watt car charger. It seems to be well made. So far, I've not detected that it's generating an RFI in the 2m amateur radio band. The springs behind the negative terminals on the side of the charger must be very stiff (a good thing) because it's difficult to insert in the lighter socket on my Ford Expedition (not a good thing).
I've noticed that Anker products are consistently well-made.
I've had the same problem with their car chargers. While it's difficult to insert, it also holds the charger tight. I installed a duplex plug under the glove compartment to give me additional 12v receptacles (GPS, charging capability, etc.) and they're not subject to normal vibration from the vehicle because they're so tight. I rarely remove them so the trade-off is worth it.
Historically, Anker products have always been excellent quality. I have mostly used 120v and 12v power supplies and have never had a problem. They deliver as advertised. While they're a little higher in cost, I find them worth every penny.