The last one. That's how I remember ThunderCoaster in its glory days. Like, you felt that the lap bar felt that gravity wasn't fast enough, and helped pull you down the hills faster than you could fall. Though, you still never touched the seat. I felt traces of that sensation on Balder, but ThunderCoaster used to deliver even more. Too bad it also beat you up, and deafened you with its mighty roar. In that departement, Balder was a nicer coaster.
^I sat down, got nice airtime, and was treated nicely around the corners. Balder is like a doctor of sorts, giving forces in well calculated doses, gives you an awesome ride, but also makes sure it's comfortable.
ThunderCoaster was more like the cook in a school cantina, who just slaps a large portion of force on your plate, but couldn't care less about how it tastes. You got air-a-plenty, but you were subject to the same level of forces in basically every direction. And where doctor Balder made sure the bends were nice and smooth, ThunderCoaster just says "you want to go from heading in that direction, to heading in this direction? Here's track"
Balder can give awesome forces if you bribe him the right way, but you'll never leave the station with bruises. Ride ThunderCoaster the same way, and if you make it back to the station, you'll need help to get off.