I just returned from a 900+ mile self-contained tour from Maine to VA on a GTO. I put that poor thing through a tortourous tour; pot holes, dirt roads, gravel roads, rumble strips. That GTO should be in pieces, but it held up just fine. You gets what you pays for.
Also what you get with the GTO that you don't get with a Trimuter is portability. Guy I was with also has a Greenspeed GTO and we broke them down (S&S couplings) loaded both of them with our gear into a rented van and drove up to Maine. Reassembled the trikes in the airport and rode out.