Agreed, having worked on a system where someone decided to implement checksums to manage change control I know from bitter experience that it will bite you at some point. I think we found numbers that were related in some mathematical way (I forget exactly) would give the same value. But we also had examples of company name strings that gave the same value.

If getting the integrity perfect is important I'd suggest not using this idea. For something that is supposed to be a rare occurrence it happened surprisingly frequently!