Second Review: We have now used all 1000 corks and have had some time in the bottle. There were only two corks out of the 1000 that did not seal properly. One had an internal flaw and one had a smaller diameter and leaked immediately. The one thing that is a little irritating is the variation in diameter. There is a variation in the amount of pressure needed with the corker. When opening a bottle, larger diameter corks require more pressure to insert the corkscrew and smaller diameter corks will actually "spin" in the neck of the bottle as the corkscrew is inserted. We have encountered one bottle with "cork taint". Other than that, they work fine. We are a commercial Vineyard, not a Winery. We do "home wine making" for experiments in the vineyard and for sales samples to sell grapes, (Oh, yes...we do drink some of it!).