The strips I bought were mounted on thick aluminum strips, then I used thermotape to mount to heat sinks and spread 3" apart and mounted the driver on top of the aluminum L brackets with just air under the driver.
Even at 100% power and running 24 hours straight it just gets a couple degrees over room temp on the heat sinks.
Overall they usually run cool to the touch.
that's a proper rig. if i ever build another it will be a strip rig.