User blog comment:Sperez2012/Mass Effect 2: Squad Talk/@comment-2256917-20120705231618/@comment-2256917-20120707225229

Yeah, I played my first game through on Hardcore as an Infiltrator. Then started reading what people were saying about Insanity, and found it much more fun. Basically, Diyartifact is right: Hardcore enemies all have protective defenses, which makes squad choice and power use mo important (which is one reason why I prefer Insanity); otherwise, as far as Shepard goes, Insanity makes it so that he or she can't take more than a couple of seconds of sustained fire, I.e. it becomes more "realistic". This fact is another reason why the Sentinel becomes more interesting a character in Insanity.

Regardless, yes, the Infiltrator is a great character for escaping nasty spots. But on any difficulty you'll have a huge advantage since you've already played the levels before. I say be bold and go for it; we only learn of our abilities by our actions.