We are all trained that should the engine quit on us (single engine) to look for a suitable landing site. I know most pilots (me included) will keep an eye out for suitable sites as part of their en-route checks.
The only time I could see a BRS system being effective (apart from structural failure) would be in the even of an engine failure over mountainous terrain where no safe landing site would be available. Of course an extra engine would help to clear terrain.