Yes i wouldnt buy from these sellers. Firstly, if it looks too good to be true, it probably is. Secondly, if you look through the seller's ratings, you will likely discover that the feedback ratings are bogus. It seems like this seller will do the following:
1) create a new seller id
2) get about a 10-12 positive feedback (probably all bogus)
3) list a highly desirable item, like the RNS-E with a very short listing (usually an auction ending within 24-48 hours), no reserve price and low starting price.
4) After selling the item, to an unwitting buyer (and probably after payment is sent), the account is unregistered.
Its a big scam, for sure. Be careful out there!