Is it really so bad?

Yes...it is pretty bad. I thought the acting was very bad, particularly by the lead actor/greedy person Willis (Russell Whaley). It was obvious that pretty low budget.
When it started I was ignoring the bad acting and chessey dialogue and actually felt there were strong similarities with "Where Eagles Dare" which was a great movie. (Allies dropping into occupied territory in German uniforms to get an important person out.). But unlike "Where Eagles Dare", very little happened once they were in except shootup and shootup.
Yeah, 4 out of 10 is about right.