Experiences with Spamhaus BGP DROP, EDROP and BGPCC BGP feeds

Hi, I am wondering if anyone here has experiences with the Spamhaus DROP, EDROP and BGPCC BGP feeds, for null routing hijacked prefixes, and prefixes which contain (only) mallicious users. http://www.spamhaus.org/bgpf/ We currently already use a Team Cymru feed for null routing bogons. Would you reckon that the Spamhaus lists offer many valid additions to the Team Cymru feeds? Did you have any disputes about prefixes that are announced as malicious use by Spamhaus with customers or other ISP's? Any responses, on or off list are appreciated. Thanks, Dennis Hagens Network Engineer AS 24875