Are there any programs that can track temperature for different vendors? I'd love to run a few ssds through a benchmark and have hard data for thermal data.
Temperature data is part of SAMRT so there's a plethora of utilities on any OS. For windows the best is HWInfo, IMHO.
Ideally, for a proper test, I'd expect thermocouples placed on the controller and not just rely on the sensor data provided by the SSD as that could be very misleading depending on where the senor is and how the raw sensor data is processed.
Will show all temperature sensors on the device, there are usually several. It also will show how often the composite temperature crossed the warning and critical thresholds in the lifetime of the device, and how long the device spent above those thresholds.
Only if the interface exposes it. USB ones in my experience outright don't support it or mess it up somewhere in the chain; the only place I got SMART reliably to work was with a direct SATA attachment to a controller.
If you have a desktop PC and want to make the process of connecting external drives to SATA for this purpose a bit easier, you can add an eSATAp bracket to your PC.
Ideally, for a proper test, I'd expect thermocouples placed on the controller and not just rely on the sensor data provided by the SSD as that could be very misleading depending on where the senor is and how the raw sensor data is processed.