Hi Meredith and thanks for your query.

In general, I don't have a very high opinion of synthetic corks. Aesthetically, they are dismal objects -- slimy, often garishly coloured, hard to get corkscrews into, hard to extract, almost impossible to put back into the bottle, and giving every impression of being ferociously non-biodegradable. I have had first-hand experience of poor-quality synthetic corks leaking, and I have also heard credible accounts of them contaminating wine with off-aromas and flavours of their own.

Any producer who wants to avoid cork should, I believe, look first at screwcap, which usually offers a better closure, which is supremely easy to re-seal, and which dispenses with the need to use a corkscrew altogether. Aesthetically, they are improving; technically, too, I understand that there are now screwcaps on the market which permit different rates of oxygen-exchange with the exterior environment, thus mimicking cork's natural properties in this respect and opening the possibility of perfect long-term storage for wines which have a pedigree of desirable bottle evolution. (Standard screwcaps provide such an effective seal that reduction problems can occur; this is one area where synthetic corks are attractive for the short term, in that they permit relatively lavish oxygen exchanges with the exterior environment -- though this can create oxidised wines with long-term storage.)

The glass Vino-lok closure is also aesthetically appealing and technically sound, at least in the short term. (The actual seal is made by a plastic ring.) All of that said, I am also a lover of beautiful, renewable and biodegradable cork and cork forests, and only wish that cork producers could solve the problem of TCA contamination once and for all. If every cork was a clean cork, then cork would still be my closure of choice for great wine. (Philosophically, I am not as bothered by bottle variation as some critics and drinkers, and I suspect there will still be a degree of bottle-variation even with wines stored for many years under screwcap.)

There is, alas, no sign that this is the case yet. Just in the last few weeks, I have come across a corked magnum of Cathiard Vosne-Malconsorts 2000 and a corked bottle of Veuve Clicquot's Grande Dame `95. I'm sorry not to have given you any help on particular brands of synthetic cork. I just don't have the requisite technical information here, though sources I have consulted tell me that Nomacork, Neocork and Nukorc are all good. Though even the names are aesthetically horrible ...