I don't know what IRM is, but for testing features or new configurations we have been directed to request a POC via our account team.
It is not the best solution IMHO as there are often changes to the configuration we would like to try out, but cannot because we only have our production ShareFile domain. It is an issue that I think ShareFile would do well to resolve. As an Enterprise customer this issue extends to our Storage Zone Controllers and UMT which we only have production versions of. No testing possible there either.