I saw it tonight as well. I found it to be an enjoyable film actually and I didn't even have low expectations. Middling ones perhaps and it reached that easily. I will say I was relieved that Johnny Knoxville doesn't ruin the movie. He has his comedic bits per the role he has but he's only in the last act really after a brief intro in the first act.
The one glaring problem in the film is:
I'm not going to oversell it despite my grade, it's a solid renter but it was fun. If this weren't Arnold I'd have waited for DVD, it was one of the few guilty pleasures I allow myself and broke my soft rule about "big screen necessity". I like my 80's action stars, I'll see Bullet to the Head
also---and that one my expectations are low.