I tried this, and I have never had such flavorful lettuce! I'd been a little worried: Hydroponics has a reputation for (maybe?) producing flavorless vegetables. And certainly, I did have trouble growing some things. But those things I succeeded with (mostly lettuce), actually had tremendous flavor!
Hydroponics, being mostly based on water and sunlight, are unlikely to boost the nutrient profile as much as healthy soil, depending on what feed you add to the water.