As a general rule, I would not be putting down heavily bonii'd wines for very long (5 years max, not 5+ years). There are reasons why the marketing people are punching the bonii...
Primarily and obviously: they need to clear that stuff!
Reading between some lines:
You may, for example, see on the back label of some such wines an importer to the UK, Europe, US etc. and sub-labelling that fits legislative requirements in such markets. They are wines labelled for export and the deal has, at least partly, fallen through. While no marketing expert, I suspect that they then can't be put back on the local retail market with such a back label. A bit like remaindered books, those wines need to be cleared. Epiqure is, at least in part, a bit of a clearing house - like many such wine 'clubs'.
There are others, where small producers can access a market that may give them exposure, or clear some stock. I've been quite impressed by some of the mixed lots offered by Epiqure. There can be some very good wines from 'unknown' producers mixed amongst a few plain offerings but, so far and selecting the super-boniid offerings carefully, I have overall been very impressed. For example, the WA mixed white and red offerings celebrating the new PER-LHR route, I thought were good wines at very good value - $ and points.
Maybe there's a wine marketing guru out there reading this that can shoot me down or can tell us a little about the trade secrets
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