I'd definitely give the nod to the olives. I used to use the orange foamies on my marshmallows when I had them. They fit very well, but only lasted ~1-1.5 months for me. They also made my ears itch sometimes. The olives feel a bit softer and are much more durable. I also have no itch issues with them. I've been using my current pair of olives for 2.5 months and they show no signs of deterioration. They still compress and have the same "memory" effect as when I first used them. Oh and since they are black, you won't gross out others like how you would if you were to pull out a pair of heavily used comply or orange tips

..or at least that's the case for me with my wax-factory ears

edit: just noticed you'll be using them with the ne-7's. I'm not sure the olives will fit on them without some modding involving the innertube. The orange foamies for the e2c's may fit out of the box. Not 100% sure though. But in either case I'd say that the small amount of time needed to mod the olives would be well worth it.