My review:
Concept: How good is idea, originality, how much sense it makes
Model: Technical aspects of the model
Performance: How good it performs in game
Usefulness: How much chances are to be used in maps
Gruntapult
Concept: A foot artillery. Although while orcs are quite strong, they maybe could carry the weapon on their head, but when launching the weapon, he would probably lose balance due to recoil. It would make more sense if they lay the weapon down, like a mortar. But still seems only a grunt with planks above the head
Model: The weapon looks rather messy, but is probably supposed to be like that (orcs). The grunt is ok, so is the uwv of the whole model. Animations are decent, except death, where grunt simply disappears.
Performance: The model has everything from events and particles, animations are well set, so it performs without problems ingame.
Usefulness: Although catapults and other kind of siege weapons looks more suitable, it still can have some use and can find use also as plank carrier
BattleMachine
Concept: A good idea, it looks like those walkers from Rise of Legends. The driver is a very nice addition, the best part is that it does not resemble any wc3 unit and it looks like a (mad) scientist. But it seems to lacks some steam exhaust or any stuff it would prove that is a machine
Model: The mesh is somewhat decent. But the texture is too monotonus, is just wood over and over again with bad uwv. And wheels are not really a good texture for the feet. Also animations are bad.
Perfomance: Because of of slow animations, lack of events, bad anims, etc, it does not really fit well the game.
Usefulness. It may find some use in many (mech) maps of steampunk styled races, but only when it will be actually finished.
Peon Pong Tank
Concept: An interesting idea, although it has some flaws. This cannot be a siege weapon as the ball could not even kill a man. In case the ball is heavy, it would break the racket. Also it creates some weird particles at the hit.
Model: The model is well made, the uwv is ok, while animations ... very basic and a sudden disappear is more like wtf for such big machine, which has almost to volatile stuff.
Performance: It performs well and stable. The ball projectile is added to fit more the model. Although sudden disappear is more like wtf for such big machine, which has almost to volatile stuff.
Usefulness: Honestly, this model has not much use, maybe in some fun maps and thats all.
SkullSiege
Concept: Nice and original concept, well fitting with skeletal beasts and similar stuff. It maybe only lack of range animations attack or ramming.
Model: the skull is well modeled, the body too. Very good use of ingame textures. Animations maybe could be better, but they are still very good.
Performance: Due to nice animation and well done uv, it looks pleasantly in game, although it lacks events(death sound), particles, and maybe the death/decay animation could be a little faster.
Usefulness: It is (surprisingly) maybe the most useful model, it makes perfect for creepy maps and undead races.
Dog of War
Concept: A not bad concept, but now we have two "dogs" rivaling, one boney and one mechanical. Only thing that looks strange are those two wheels, where the machine looks like is floating as it cannot keep the balance with two side wheels. Nice ideas for the animations
Model: the model is kinda simple, but it may work. The uwv could be better, there are much areas to fix. Also the texture chosen is not the best, those yellow lines are annoying (psst, use blacksmith instead). The animations are decent, much better than in your wh40k models, but still needs improvements.
Performance: Its behaviour ingame is not how it could be, the main reasons are slow spell animations (unless you give a huge value of cast spell in object editor) and bad death animation, which causes a fissure way too late. But at least the sound events are there and particles are very well made.
Usefulness: It reminds me of sidereal engine, good for futuristic maps with robots and stuff.
Currently, I would vote for Werewulf, but I will wait a bit, now the creators can correct me, if I said anything wrong.