Very suspicious
You can go to the manufacturer's web site and download the user manual. I did that, and was bothered by what I saw. There is a diagram accompanied with instructions recommending that you use your receiver's subwoofer output, and they state that when using that output, to follow the instructions for making settings on the subwoofer. Note first that this single line-level, RCA input is a single input for the monaural subwoofer, and is not compatible with a pair of line-level outputs for the main speakers from the receiver. Since you don't have a subwoofer output, you would want to use the speaker-level outputs. That in and of itself is not a problem, but there are other issues given what I saw in that user manual.
I could not find anything in the manual that said where to set the crossover frequency for the receiver's subwoofer output, and it strikes me as odd that they would recommend using that output but not advise you where to set the crossover frequency. Moreover, I expected that for this connection method, there would be a switch on the subwoofer to bypass or disengage its internal low-pass filter. But there was no mention of such a switch, and it would be very difficult to get the subwoofer and the satellites to blend properly using both the crossover in the receiver and the crossover in the sub unless you know the crossover frequency of the subwoofer and set the crossover in the receiver to the same frequency. Most subwoofers that accept speaker-level inputs also have speaker-level outputs, and the signal at those outputs is passed through a high-pass filter to insure that the satellites are matched up properly with the subwoofer. But this subwoofer does not seem to have that. Most small satellite speakers need to be connected with the use of high-pass filtering, lest they be overdriven by the bass energy in the full-range signal at the main speaker outputs. Most newer A/V receivers will provide that, either by giving you a way to specify that the main speakers are "small", or else applying a high-pass filter that is aligned with the low-pass filter for the subwoofer output. But if your receiver does not have this, and the subwoofer does not provide it by providing high-pass outputs either at line-level or speaker-level, then you have to wonder what will prevent the satellites from being over-driven by the full-range signal output from the speaker-level outputs of the receiver amplifier. This likely explains why they recommend using the receiver's subwoofer output. But given that, the subwoofer should have a switch to by-pass its internal low-pass filter, and the fact that it does not have such a switch, makes you wonder whether it even has a low-pass filter. This is especially curious given that they promote an ideal match between the subwoofer and the satellites. It comes across to me as a case of marketing trying to mask a product's flaw by touting it as an advantage. I get the sense that this is not a good product, and I would be reluctant to bother with it.
