I've stopped by the Umami Moto truck a few times now, and always had a great experience. Everyone there is always friendly and helpful, and everything I've had to eat has been sensational.
I just had the pad thai for lunch today, in the medium sauce and ponied up the extra two bucks for the shrimp, chicken and tofu added in. Great portion size, I struggled to finish it all and awesome flavors with just the right amount of kick.
I tried a coworkers chicken curry and while I've never been big on curry, I really enjoyed it. The curry wasn't overwhelming as is usually the case IMO.
Finally my favorite is the bahn mi. While I agree with another reviewer that the french bread roll may not be the best choice for the bread, there's no denying the flavors going on here. Huge portion of tender marinated pork and all the fresh veggies with the special mayo sauce. Go with this one and try the other options next time around.
Umami's got my vote as best food truck in Cleveland.