Ultrafire C8 SST-50 De-domed

Hi guys, i'm a complete noob and don't know half of the lingo so forgive my ignorance in advance please. I just bought the above light and whilst inspecting it and playing around i screwed the reflector down onto the led causing the dome to come off, now i now know that it's purpose is as a lens but my question is, is it necessary? I plan on using the light mainly for mountain biking at night. Now to me the beam is better dispersed as well as brighter in its dispersion and at its focal point albeit with noticeable halos now. However i only tried indoors pointing at the ceiling so i don't know what it would be like for the intended purpose. I have been offered an exchange but i thought i'd just get some feedback from the guys who know p.s its supposed to be the 1250 lumen model which i know is an unlikely output. Thanks very much