That is a great bar price for Louis XIII; the last bottle I bought was over USD 1000 and that took considerable searching.

As cognacs get older and more expensive they become lighter, "fruitier", more fragrant but with less body, more like perfume. This is why most very old cognac is used for blending with much younger ones. The bottom line is that old cognacs are so verrrrrry expensive not because they are better tasting, but because of their rarity and high demand for prestige value.

You might prefer something like Martell Cordon Bleu, or if wanting to try older and lighter but still with excellent body, Hennessy Paradis. Most likely the ultra-premiums like Louis XIII would disappoint you. It is an acquired taste.

Personally I prefer old (and expensive) Calvados; but hard to find outside of France. Better than most cognacs. Also the grape eaux-de-vie made in Germany (mostly Rhine valley but some Moselle) are superb; they are like cognac but clear (due to different aging) and of course made with better grapes than cognac has