Great design, Poor in execution
For those of you bored with the easy levels early on, the game becomes EXTREMELY HARD starting from the fourth to last level. To put things into perspective, at the boss has 2000 + 1000 HP and at its final stage you can only do 1 damage against it with your normal attack in tank mode. So if you didn't save enough money for 8-9 bombs, a dozen missiles and 6 tank transforms, you might as well just give up at the final level and call your time wasted.
As for the review, the main problem is that this game wasn't executed well. Gameplay is extremely slow and that just adds to the frustration in the last level, when you know what's going to happen but the game just takes forever to get going. Due to the slow pace of the game, many players will quit before reaching the last four levels, which is a shame because that's when the game is really about tactics (or actually, the patience to watch the slow-paced action unfold).
The interface is well-designed but another problem is that this game really isn't logical when you see people with bows fighting tanks and helicopters.