Am i the only one cursing this level? its so terrible hard on Secret Agent. I finally beat it today, after i had tried for a few days, i was just about to complete it but the game somehow forgot my check point, very annoying!

They don' t have as many checkpoints on the harder levels, sometiems there aren' t any.

Once you get up to secret agent things get annoyingly tough because you pretty much have to beat the whole level without dying.
I think the last level before the boss game me the most trouble. Trying to cross that bridge was insane. I thought the end boss was kind of easy.

There always seems to be some trick to beating parts of the game though. You can do it the hard way with brute force or you can do it the much easier but still sometimes hard way with the trick.