I have used them for the last 8 years. Four years when I had a winery and the remainder as a home winemaker. they hold the wine very well after opening as they become a air tight "T" cork. they are a economical alternative to corks and a shrink cap if you desire a decorative touch to the wine. It was a great seller and conversation starter in the tasting room.
they can be inserted using a bung rubber headed hammer, or if you have a lot, I use a beer corker with a two inch magnet attached to the beer capper. adjust the height and press down similar to beer capping and the Zork is easily inserted.