Somehow in Lithuania we do have 2 masters who works with cartridges. I do know both in person. And had an opportunity to listen of some of their works. One of them is my friend and once he did prototype in two versions one nude 0,5 mil conical another is contact line. Manufacturer was the same Namiki as I do recall from my memories. And CL version was inferior from the first shot. So it's not so easy to get into. It's like a cuisine in which you are extracting taste with different additives.
And if you'll look into low compliance and LOMC cartridges sometimes cuisine leads conical profile. Perfect example is Denon DL103 with 0.65 mil conical. Weakness of Denon DL 103 isn't the conical tip itself but as it mass product it has huge variation of quality from sample to sample. Some of these are really good ones, some of them are bad ones. All is the matter of taste, like in cuisine.
As about lifetime of tip you are right. But better to check is it nude polished one or bonded one, it gives better quality idea. I won't change 0.5 mil nude conical into 0.2x0,7 elliptical bonded in any case.