Torso to head reminds me to Macross. The weapons are AC's. And the whole style makes me think it's like the Eva Provisional unit, but to know that this is from AC, that's enough to make me go back and find some more AC kit XD
Are mecha practical? Obviously the technology is not there yet, but even if we could build them, would not tanks just work better? Go faster, go over most terrain fine, have far better armor because of their shape, use less energy for the same movement? Well, if Mecha are practical, I bet spider designs, like this one, would work much better than bipedal ones like gundam and such.