• I like the concept of using a guid as a pseudo random number. Very novel approach!!!

    I've always used auxillary tables in tempdb combined with forward-only cursors to assign unique, random numbers to each record for setting up direct marketing test panels...I generally do not use cursors but this was quite fast for my needs and direct marketing / database marketing queries are mostly ad-hoc in nature anyhow and my systems have not had to worry about performance hits like a production OLTP system would.

    This alternate approach you outline IS going to get tested.

    Well Done!!!