I've seen it and can tell you that I loved it the first time I saw it, thought it was crap the second time I saw it, and then felt somewhere in the middle the third time. I couldn't explain that if I tried.
Please note: Alberto De Martino does NOT make quality films. However, he has managed to make some entertaining ones from time to time. This one is certainly not one of his worst and is probably one of his best. But one of *his* best isn't saying too much.