banerjek - if you were on a Terratrike and it seemed like it had squirrely handling, especially at speed, it might have needed the toe of the front wheels to be adjusted. If that is not right, any trike can be super twitchy. Toe is the allignment of the front wheels, if they are parallel, or closer at the front or at the back.

I know the OP was about a triker, but since its drifted into a comparison of DF (bent riders call regular bike DFs, for diamond frames) and bents for performance and aero, I'll mention this. A good comparison of the DF and bent platforms is in this post on my website, by an avid cyclist/ex-racer/healthy/youngish/non-disabled/strong cyclist who wanted to fully understand the bent platform by committing to it for awhile. He rode one long enough that he fully understood the differences, and never went back to DFs. His story is here.