General advice is that basically every speaker can benefit from integrating a subwoofer properly.
General advice is also to have some way to apply a high-pass filter to the main speakers, either through a miniDSP (or similar) or an AV receiver.
In your case, looking at the speakers you mentioned, they only have 5" woofers, and the manufacturer only specs the "frequency response" (which, the way they spec it, is a completely arbitrary value) as 40hz on the bass side. Both of these indicate that this speaker isn't designed to be a "bass monster".
So yes, if you are listening in anything bigger than a closet, then you will definitely benefit from a subwoofer.
However, integrating the subwoofer properly is critical. If it is not integrated properly, it can noticeably downgrade the sound.
There are lots of resources out there about how to integrate a subwoofer properly, but to start with, you will need to account for room modes (either by measuring and "brute force" correcting them, or by adjusting the subwoofer / listening positions), then you will want to set the subwoofer's low-pass filter appropriately. Ideally, you would also high-pass the main speakers so that only the subwoofer is producing the deep bass, and use EQ to correct any room modes above the crossover frequency as well.
My biggest recommendation for an upgrade would be some kind of measurement system, like a UMIK-1 and REW, as well as DSP/EQ for your main speakers if you don't already have it. This will allow you to correct for any room modes (basically room resonances, usually sub-400hz in "normal" sized rooms, which are not feasible to absorb with acoustic treatments, and can be very audible).