I do hunt with my peep sighted flinters
BPS, and with two peep sighted caplocks (GM barreled TC Hawkens in .50 and .58). I don't have any difficulty with them in even thick pine woods with any reasonable light. Peeps do suffer during that golden time just after first light in the morning and right at dusk. Though it may still be legal shooting hours and you can see the game well enough to identify it, you can't see the front sight well through the peep to place the shot. I fix that little difficulty with my sight light, which goes on the barrel during those brief periods.
http://www.huntingnet.com/forum/blac...ight-dusk.html