Last January I reported on the Machin trials produced by Hélio Courvoisier SA of Switzerland in cooperation with the House of Questa. Ian Billings also mentioned it here.
In the June 19 issue, Linn's reports that the three sheets of 100 subjects sold for $15,000, including the buyer's premium. The article also notes that another set of three sheets will be auctioned by the same firm, Daniel F. Kelleher, in late June.
The article also mentions that a total of ten sets of three sheets were produced by Courvoisier in 1997. With the two sets being sold by Kelleher and one set donated to The Postal Museum, there are seven sets left unaccounted for.
Linn's original article on the trial panes is here. The realization article does not seem to have been posted on their site yet. I will update this post if the article appears on their web site.