Most smaller clearomizers use the outer threads, which are much better structurally, especially for portable use. The 510 connector is good with all steel parts, but when the expectation is to use the eGo thread, they usually aren't. I think it's usually chromed brass on both sides. The Nautilus Mini is a bad design at this point as a portable clearo because it doesn't recognize this, vs. the Kanger mini Protanks using eGo even though the fullsize uses 510. I actually think the tendency for everything to use the 510 is to avoid association with eGo type devices.
As to "cheap crap" etc., I saw a review with a complaint that with a $10 starter kit only 5 out 7 worked. While this was inconvenient for someone getting gifts for 7 people, having one of them myself, I can say that a working one is as good or better that anything else you can get for its size OR you can get for $14. Just to put things in some perspective....