The LopoLight you linked to does not have the
anchor light option, whereas the OGM does. I didn't dig far enough to find out whether Lopo offers an
anchor light or not. My recollection from a year ago is that the Lopo unit was more expensive (about double the price) than the OGM light, but that may have changed. I have the OGM tri-color with
anchor light and photodiode, but not the strobe option. It has been excellent so far, and I am very happy with it.