i think it'll be "safe"(er) to use unprotected batts in direct drive lights (as opposed to regulated) like the Orb RAWs, because you will notice when the light starts to dim and thus know that you have to swap batteries.
with regulated lights like the P1, i'd not feel safe using unprotected cells as the regulation circuit will try to drive the battery as much as it can to provide you with constant brightness (as much as possible). so because of the regulation circuit, you won't notice the drop in brightness to tell you when to swap, and you will also be driving your battery hard all the way. both not good when you consider that you want to avoid overdischarge in li-on cells as much as possible.
p.s. you will of course notice an initial drop in brightness on both protected and unprotected batts, but i think that's more because the batteries come hot off the charger at around 4.2v, and will settle down after that drop.