Softride is still in business. They're still making bikes. Early on, they used to make MTBs as well. The MTB version was nicknamed "the catapult" by many riders because under many circumstances, they would get bucked off the thing. The roadbike is actually a much more reasonable application for the beam seatpost. Also, there are a few tandems that use the Softride beam seatpost in the stoker position with the design under license from Softride. Here's one of my riding buddies with a mid-1990s Softride 700.



Here are newer Softride roadbike models (they make several different kinds).