Its not a habit. A lot of the stuff I buy is spares or repairs so when the engine is full of shrapnel the car's history is pretty irrelevant! It might have been prudent to check the S8s, but it didn't even cross my mind tbh.
It would be useful to have documentation for the FE when it comes to sale time though, since it might provide peace of mind for any prospective buyer. Its had a couple done in the past as its had a few plate changes so an up to date one wouldn't hurt.
We did check Lucy's TT before buying that, since its a prime candidate for being stolen or accident damaged at some point and I'd spotted a wing had been painted so we wanted to make sure it was nothing major.
It may be a service I'd use occasionally when buying or selling something valuable
