There are substantial disadvantages, too.
In order to take advantage of the greater port-density(-per-dollar) on FR switches right now, the end user has to use FR, which is not always practical or desirable.
One of the reasons why end users find frame-relay undesireable is that they cannot be assured that their provider is not grossly oversubscribed on PVC-per-port density. When you buy a T1 private line, you can be assured that you're not sharing it with 120 other end-users. :-)
Nor can you know that with a Dedicated line, that the other side doesn't feed into a 2501 into a collision-ridden Boca 10baseT hub, into a Welfleet bridging over Frame-Relay-over-ATM at 1.5Mbps simplex speeds into an over-committed 4Mbps port speed on the other side. i.e., the fact that your buying a leased line to connect and running HDLC over it doesn't count for anything. When it comes right down to it, customers can't really be reassured of anything. But then, nobody expects the customer to realize this, right? Dave -- Dave Siegel President, RTD Systems & Networking, Inc. (520)623-9663 Systems Consultant -- Unix, LANs, WANs, Cisco dsiegel@rtd.com User Tracking & Acctg -- "Written by an ISP, http://www.rtd.com/ for an ISP."