The reason I bought the the Suhr RL is what my topic reads. As a Kemper user I have my own IRs (Profiles), plus the built in ones and you can easily import any IRs to the Kemper. So there's no need for me to have an active load box with built in IRs. This one has everything I need; DI Level knob and the necessary outputs on the back.
I LOVE THE FACT THAT IT'S A PASSIVE DEVICE i.e. it doesn't need its own power to run. The built in fan is powered by the high current signal from the amp; the more power (Volume) you feed it, the more the fan runs. I ususally run low powered amps into the box so the fan usually doesn't run at all for my applications. Although it should be noted that when it winds up it sounds a bit weird, like something is broken, but it's not.
I'll give a 4 star rating for sound as I'm still a firm believer that a miced up amp sounds the best. An amp through a load box is the next best thing and something like a Kemper alone falls at third place.