Not for travel, but I do use Pleco at home, mostly for figuring out Chinese newspaper headlines or specials in Chinese restaurants that are written only in Chinese. It's fun to use. You can even enter in handwriting and it will try to figure out what Chinese character you are drawing. But I can see how it would be frustrating to use while traveling if you wanted to understand something quickly. In 'real life' we don't often have the time to wait to get the correct translation. By the time you figure it out, the moment's gone.
The most important thing is to be able to get back to your hotel or to get where you'd like to go in the first place. For that, you should always carry the business card of your hotel with you. For other places, it's best to be able to pronounce the name or location (nearest intersection) of where you are going in Chinese. It's not difficult once you get the hang of it, but ask at your hotel.