One advice: after you bought all area 1 parts farm it till you got about 30k cash (2-3 flights) so that at area 2 you already have enough cash to buy all parts instead of starting from zero and climb slowly.
So many whiners o.o...this game has no flaws. You can complete ALL levels with 2-3 tries ALONE (the hard ones) and even finish few levels on A rank.
And if your controllers lagged/sticky then try to close unnecessary programs because I never had that or any other problem with this game.
So frustrating to get "Ace III" and "Good weather" achievements :|...
Oh and how exactly do I get "Speed IV" ? I tried to use booster+accelerator but still nothing.
BTW this game need badges!
Totaly agree with LordKevin. I had so little time to learn the game and lost at 10th wave.
Not sure about others but learning the game by lossing 3+ times isnt my style...
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