The competitor product you are comparing to is a much lesser product in terms of quality. The WD Live uses a better, revised chip revision. Faster too.
The other competitor products have licensed this from the start - for WD Live they meant it more as a media player not a DVD / BluRay player - I have voiced this concern many time both directly to WD and inquired about it to Sigma, and both have told me that there are licensing fees required. For the chipset maker, it would have increased the cost per unit for WD, and thus, made the WD Live more expensive. So I have been told FULL DVD and BluRay spec is very unrealistic and not to be expected on the current WD Live - #1, it would be costly, #2, would require a major re-write (takes time and resources they don’t have!)
Partial DVD specs as in chapters, goto, SOME menu functionality, again, that is something that is unplanned for now, but being discussed and but unlikely to be seen anytime soon or at least not for the current hardware.
So to me this is a lost case - Fact remains for me that the WDLive has the better chipset that others don’t have, and better quality - I can live without dvd menus - I make my OWN when I RIP the DVD and manually rename what I want to and set them in folders. No big deal there.