We do not run ChexSystems (QualiFile) on either of the customer types you mentioned. The only benefit I could see to doing so (since one would not expect a chex record on a child or a rev trust) is verification of information given (i.e. address, TIN/SSN, etc.). Aside from that, probably not worth the additional cost.
We do run QualiFile on business customers, as they do provide chex records for them.
Nothing changes, if nothing changes. (from a good friend of mine)