I have seen a good quality using them, Comcast uses it and I get better pings to the Datacenters that have them

And I think its one of the top global IP owners too

The Top Ten Networks Defined by IP Addressing Control
Rank IP Space ASN Description
1 85,990,619 721 DLA Systems Automation Center
2 44,675,577 3356 Level 3 Communications, LLC
3 34,518,858 701 UUNET Technologies, Inc.
4 32,819,303 7132 SBC Internet Services
5 27,967,615 7018 AT&T WorldNet Services
6 21,661,786 174 Cogent Communications
7 20,890,035 17676 Softbank BB Corp.
8 18,561,735 237 Merit Network Inc.
9 18,001,873 71 Hewlett-Packard Company
10 17,875,993 7474 Optus Communications Pty Ltd