How long should it take to install sp1b on a three-node cluster of new
servers which is running one virtual server?

This thing has been running for almost two hours now and, while it's
making progress, it's taking much longer than I expect it should.

I've watched it install on the virtual server, then node 1, then node 2,
and it's now on node 3.

Should it REALLY take this long? I have my workstation AV turned off,
have a 100Mb connection.....