xfer data from prod->test->dev

In our shop, when it times to refresh our test and dev databases, we take the unload files from prod and simply load all data into test/dev. We can do this because we have very little data (<10gb). However, going forward, this is not going to be practical approach (our business is growing; so is the amount of data!). One approach to take is to maintain a script of all tables from your production database that unloads a sub-set of data from all tables. The unloads can then be used to refresh the test and dev environment. (This approach may not work if you use RI) What approaches have you taken to refresh your test and dev environments? Thanks. Steve Romankiw