For me it's all upside on skin and hair. The only downside was that it was initially set too soft, which negatively affected taste. I tuned into until I got it so that it tastes fine while also being great for skin and hair.

Do not drink soft water. The high sodium content messes with your hydration balance. Better to drink hard water, before the softner (despite what they tell you that soft water is "fine", it's not fine). If your water is between 15 and 20 grains of hardness this is ideal for drinking. For showering, turn the softner to match your hardness. Also, get a resin cleaning acid drip, it keeps it functional and long-term reduces amount of salt used.