You are not alone in thinking so, I find this N.Cicero's film very enjoyable and well-directed in his intentionally exaggerated approach.
In my opinion Professionisti per un massacro is vastly superior to Il tempo degli avvoltoi (apart from the conclusion) and outmatches Ammazzali tutti e torna solo in everything.
I think it doesn't really work in its tongue in cheek approach
Usually I'm not a fan of this kind of approach, but to my way of thinking here it works in a big way. Maybe the film suffers from a bad English dub...