Sorry, I missed this before. I find their reds age quite well-- I prefer cellaring them a bit. Young, I find they can sometimes be a bit tart and reticent palate-wise (a decant really helps), though they always have a great nose. Just had a 2013 Eolithe and it was much better than on release-- felt deeper and more balanced. We bought a 2011 Cabernet Sauvignon (!) while visiting last year that felt like it still needed to cellar for some time (it was 11.5%, btw, which was interesting for a Cab). Not sure how long you could go with these wines, but Loire reds seem to have a really long runway in my experience.
Not sure how the whites, like Arcane, age. I’d imagine they can last (and improve) for a number of years.
2015 is a nice vintage for Eolithe. I liked the 2014 also-- bought some at a tasting at Weygandt, but haven’t opened one since.