I only watched the opener of the first episode and I can tell you that the way he beat the palm scanner with dust was ludicrous, you can't block bullets with a cheap drink tray, you can't knock someone out by throwing a cheap drink tray like a frisbee, high quality digital headsets aren't fooled by a simple electromagnet, and boats don't explode like that when they crash.
All that stuff happened before the opening credits. That being said, I'll be watching a few more episodes soon. I would enjoy more realism in MacGuyver, but it's not a requirement.