Hi Cogito! No, you're not the only Metaxa fan. I was introduced to the 5 star on Mykonos by my Greek colleague in early 1970s, and I've been an avid fan ever since. However, about 3 years ago I bought a bottle from a shop in Bingley West Yorkshire near where I live and the flavour had changed dramatically. You say you can remember what 5 star tastes like -buy a bottle now and tell me what you think. It has changed from a lovely fruity flavour to something like caustic soda.
It was so bad that, after first thinking my taste was off that day and putting it away to try later, I found later it was not my taste. I know one's personal taste capability can wane with the years but this was so bad that it wouldn't even mix it with dry ginger (sacrilege I know, but I was desparate!). No kidding -it was so bad I couldn't find it in me to give it away, I poured it down the sink, would you believe.
What finally got me into action was another colleague, who knew I was a Metaxa fan, bought me a litre on his Crete holiday, and sure enough this was also bad -a whole litre. I thought I'm not pouring this away so I got in touch with Metaxa and mailed it off to them for analysis. They wrote back saying "It has not changed significantly". I said the change was bad enough for me to pour half a bottle down the sink and, as a research chemist, I offered to look over their results and point out where they had gone wrong free of charge but they declined.
After waiting further, in vain, for some token of compensation for the litre I sent them I asked point blank, and they have now sent me a 70cl bottle of their new stuff -12 star, just received today. It tastes very much like the old 5 star I've always known, but it's more expensive.