Yeah, glass is actually one of your better bets. Two of the 5-15 survivors of free fall incidents fell through glass roofs. You can read more here: https://en.wikipedia.org/wiki/Alan_Magee
The problem is that you're hitting water at 120mph. A 60mph impact of a 50kg person is 35kJ; a 120mph impact of a 50kg person is 150kJ. That's 4.5 times the energy. I'd almost certainly choose water (with a streamlined, pencil dive profile) over concrete, but that doesn't mean it's not going to be far more fatal than any other options.
The water/concrete thing is just a simile, not a statement of fact. It's not meant to be "hitting water at X speed is like hitting concrete at X speed" - otherwise we'd have a lot of dead high divers on our hands. It's just meant to mean "hitting water at high speed isn't very forgiving".
https://youtu.be/yGJqqDaKscQb - 'Mythbusters for the Impatient' video showing dropping a pig onto concrete vs water. The concrete drop actually decapitates the pig!
...and if you have to hit water, close you mouth, hold your nostrils closed, and clench your buttcheeks together. Basically, you need to close all holes into your body that are aligned in such a manner with the water - it will force its way in greatly. The last tip - do that because you don't want a ruptured bowl/intestine...
The problem is that you're hitting water at 120mph. A 60mph impact of a 50kg person is 35kJ; a 120mph impact of a 50kg person is 150kJ. That's 4.5 times the energy. I'd almost certainly choose water (with a streamlined, pencil dive profile) over concrete, but that doesn't mean it's not going to be far more fatal than any other options.