First, the photo above is the model of the series II (PL-Pro / E II). The former model described here, the PL-Pro / E does not have BNC socket for connecting a light to the rear, and on / off button on rear terminals is red instead of blue) A Other than that, it's the same.
While this product is neither more nor less than a power strip (10 out the rear, 16A, 220V) all in 19 ", 1 unit.
This kind of device is designed to be placed on top of your rack:
1 - plug in your gear while protecting it from power surges and eliminate some high frequency noise.
2 - turn your entire rack at once with a single switch (useful for some devices with a switch on / off the back - once in the rack switch on the rear, it's boring)
2 - have two small telescopic small lights that can illuminate your rack on dark scenes or in your home studio atmosphere of subdued lighting
So I have not tested extensively clean the gain of the current delivered at the output, simply because I do not have the equipment needed to test this "clean"
Please note that this device does not regulate the output attention, if you have changes in input voltage (which is the case in most places can, thank you EDF) you will have the same variations in output. on the other hand, a nice thing, the LED tells you the input voltage in steps of between 180V and 280V 4V. If the voltage drops or rises beyond the range limit (220V - 240V) the appreil is supposed to be protection (again, impossible to test)
Clearly, I use the convenience "strip rack" and that's all.
After if it protects more of my stuff overvoltage, the better.
edit after 2 weeks of use
By connecting this unit, I realized a big buzz. Ironic given that this device is supposed to clean the stream and make a gain of silence in buzz and hum on some other sensitive devices. In a context studio, or silence is golden devices is not acceptable.
The buzz comes from two noisy transformer inside the unit. I had to open it, unscrew the transformer housing and place silent block (small adhesive foam expensées to absorb vibrations) I must admit that the contruction inside is neat, but frankly the scope of the transformer that vibrate, screwed directly against the housing end and resonant, it's not class. Now, with the silent block, no worries.
I see the use if this unit really makes service or not. I will return if necessary on this view.
edit after 1 year of use
This rack is his job. I confess that I found a gain of cleanliness by plugging my guitar amp on the rack rather than directly on the sector.
More and other small plop noise here and there ...
on the other hand, you really have the need for such a product (may be someone who travels a lot, being unsure of the electrical conditions we will find, or even someone who leaves become permanently connected all his stuff and want to protect it from overvoltage (personal, I have a big circuit breaker that I cut at the end of repeat)
In my case, it's not super useful. I plan to sell it.