Which charging cable is better for my new drivesmart 55?

 

I have a gtm-60 from my 3590 and the ta-20 that came with the DS 55.
Both work, but which one is better suited for the drivesmart 55?
If the DS55 doesnt get digital traffic and only gets it through the app I might as well give the gtm-60 to my dad (whom I gave the 3590 to)

Check your model

Check your model. If it doesn't have LMT, then traffic is smartphone only.

From page 13 of the manual:
Product models ending with MT can receive traffic data from
an over-the-air broadcast signal using the built-in traffic
receiver and the included vehicle power cable

--
DriveAssist 50 (stolen), Nüvi 2595LMT

Cables

Since the DS55 came with a TA20 cable, the traffic receiver of the GPS is built into the DS55 itself and the TA20 only serves as an antenna (plus charging, of course) for the built-in receiver. The GTM-60 is a combo traffic receiver/antenna/charging whose primary use is for Garmin GPS devices with no built-in traffic receiver.

As already stated in the earlier reply, if you have the Garmin Drive app on a smartphone and have the smartphone near the GPS, the Garmin Drive app's traffic will override either FM radio-provided traffic.

If your dad lives in a large-ish city with FM broadcast stations providing traffic, then he'd benefit from the GTM-60 on his nuvi 3590 and be no loss to you if you use the smartphone app.