I have no clue how much time I have on there, but with two and half playthroughs, it's got to be a nasty amount.

If you plan on getting the perfect ending with 100% and such, expect to spend a long time.

And it really isn't hard, unless you plan on doing the sidequests.

Which make up the majority of the game.
(I found the stupid lightning rod towers game harder than the entire via infinito)