It was a GOOD series
I don't know if the BBC aired a version different from the one aired in the USA on A&E, but I liked "The Borgias, and have watched repeats and tapes of old episodes with pleasure through the years. Considering that all but two people on IMDb have rated this at "7" or higher (which yields a "weighted" score of 5.9, which says something about the reliability of these scores in small samples!), I'd not hesitate to reccomend this to anyone with an interest in the Renaissance.
Is it a soap opera? Yes. Is it "notorious"? No. Is it good? Yes.
Talk is cheap. Movies are expensive.