I think this depends on your preferences. I like the Balvenie range, and that is easily available in 8, 10, 12, 16, 18, 20, 25, & 30 year old varieties.

For sure the 30 year old bottle is €300 compared to €30 for the 8 year old, and it is hard to rationally say that it is ten times better, but it is _different_ and it tastes great.

I'd never pick a bottle based purely on the age, but there are differences and I personally tend to gravitate to the 18+ ages when I'm picking my single-malts.