I've got what I believe is an earlier version of this loader, boxed as a "Telesar Computerized" loader. Unless you attach the film to the spool in total darkness, there will be some fogged film at the end; however, depending on the space between the cartridge and your camera's shutter, there could be little or no fogging on your final frame. That said, on mine, there really is no light trap per se; instead, the film passes through a couple of narrow openings and around a bend. This means that there can be some fogging within the last couple inches of film, although this can be minor or minimized depending on how bright your room light is and whether it shines directly into the loader's opening. (I'll try to attach an image that should help illustrate this point, with a scrap of film to help show the film path.)
Worse than this, because of the turns that the film takes through the loader, the emulsion side passes along some plastic parts of the loader. Although I successfully loaded an entire 100-foot roll of T-Max 100 with this loader, I got scratches when I tried to load some Fomapan 200. I don't know if I just got a bit of dust or something affixed to the "walls" in the loader between these two rolls or if the Foma has a softer emulsion that's more easily damaged. Either way, it's a serious problem with this design.
All that said, I don't know how similar the current models are to the one I've got. If the basic design features are the same, I'd say that the loader isn't really an improvement over the traditional Watson and Alden designs. At least those models don't pass the emulsion over plastic parts. If the newer AP/Arista/Bobinquick model has improvements to keep the emulsion away from the plastic walls, and ideally also an improved light trap, then it might be worth getting. Can anybody who has one comment on these issues (comparing to my sample photo)?