It's a lot of work, yes. But you have to be fair. There are worse games for achievements. Ever play the game Devil May Cry 4? 80+ hours at a straight barrel-through. Metal Gear Solid IV? Hells longer.
GTA IV was much worse.
So, it's not a "too much work" as it is, "does your card deserve to have this achievement on it?" I'm guessing not.
Signature courtesy of Slaughter