I don't know much about imaging reflection & dark nebulae with unmodified DSLRs but I would have thought it wouldn't be an issue (looking at AstroBackyard's
post as an example).
The LPS-D2 is supposedly filtering out LED light however I'm not keen on the green colour cast so I haven't used it much. I tend to lean more towards the LPS-V4, STC DuoNarrowband, and now most recently with last night's test am liking the new NB2/NB3 very much.
Whilst typing this post I'm currently imaging the Helix Nebula more with the new NB filters.
My filters are all 52mm for use drop-in filters. I don't actually have a non-modified DSLR - even my Nikon is a D810A, so I can't test the filters on a non-modified sensor.