Good and easy enough to splice to a 3 prong plug with some easy twist wire caps and some form of strain relief (cable gland, or something).
It costs more than the plug in, you have to buy extra things to make it work, and if you don't stick it in the wall, all these points are a clear detriment compared to the plug-in. But what it does have over the plug-in is availability, likely due to everyone wanting the better product (plug-in) and leaving this one well-stocked.