Yes, of course, we are all have a debt of gratitude to Erowid; it a invaluable respository of knowledge about drugs. I am personally indebted to them for their efforts and I am sure I will be for years to come. Erowid will provide a record for history of an aspect of human knowledge. (Sometimes I wish they would edit and select more rigorously though...)
The "Explosion" article:
(a) "Implosion" (see picture of flyer) was advertised as for sale, but was really a flyer for "Explosion". Some flyers contained statements about EMM ( I assume to avoid mentioning the real contents). This one actually says its for "Explosion" and was distributed by a smart shop:
"Explosion: ....
170 mg EMM (4,5-dimenthoxy-2-ethoxy amfetamine)..."
Reading comments in forums, people knew all along that it was methylone. I think the Erowid article may be confused by the the "advertising": "Confronted with these findings, the manufacturer began selling the bottles as 180mg methylone." (Erowid) The quantities for EMM (fictional) and Methylone seem to have got mixed up.
As far I have read, it was always said that "Implosion" contained 280mg of methylone, although subjective reports have placed it at between 200mg and 250 mg, as have air drying the contents of vials.
(b) "Methylone Impact" is sold in Japan, but I can't see any evidence for its sales being directly related to those of "Explosion" (I have no personal experience with it)