The PH50D is a different light. The PH50 has not been made for a few years. The bulb burns at 30 W and 50 W, temperature 4300 K, 4500 lumens (at 50 W). We don't have the illuminance information at different distances (hahoo question). Factory has been notified and we will repost when data available. as noted on Polarion-store: usable range depends on atmospheric conditions. Rain, moisture, dust, all contribute to shortening the range of any light source (by scattering the beam). We don't comment on other products but in general, Polarion has a good form factor (shorter reflector assembly, more balanced weight). It's not a modzilla light but a great tactical light that meets to needs of the most demanding end-users.