As long as the liners have holes to allow excess water to drain, I see no problem at all with them. Hanging plants require more frequent watering, in general, because the container is surrounded on all sides by air. With a wire container and only a coco liner, that would allow moisture from the soil to evaporate quite rapidly from the entire surface area. I think using plastic liners would be a smart move, myself.
If you use the plastic liner, the possibility exists that the plants won't need to be watered every day, except when the temperatures are high. During the first season using plastic liners, you would probably need to monitor the moisture of the soil, rather than just watering on a certain time schedule.
My petunias are in plastic flower boxes with just a couple of drainage holes in the bottom. They still need to be watered a couple of times a day during very hot weather, i.e. temperatures in the high 80s and above. Fortunately, very hot weather doesn't last long where I live, usually not more than a couple of weeks.
"Isn't it enough to see that a garden is beautiful without having to believe that there are fairies at the bottom of it too?" - Douglas Adams