In my practice I am asked this question all the time. Usually the patient asks why can't you place a large filling for now and I will do the crown later if I have a problem. This is not a particularly good option since very few patients will remove a functioning permanent filling to place an 'elective' crown. Instead they do wait until something happens to the tooth. Usually one of two things eventually happens; Either the tooth experiences recurrent decay( Large permanent fillings can be hard to execute optimally and can be more prone to voids and recurrent decay) or the tooth fractures( large fillings do not protect teeth well from fracture).
Instead of a large permanent filling I recommend a large Miracle Mix restoration. This matereial is made of a combination of glass ionomer cement and the metal fillings from amalgam(leaving out the mercuray). They are "kind" to the teeth they restore and seem to inhibit recurrent decay. Their drawbacks can be that they can be difficult to achieve good contacts and they are more brittle than compostie. They work well as an intermediate type filling and can last from 6 months to several years or more.
I use bitine rings (or analagous device) to achieve optimal contacts. I have used this restorative for 15 years or more and when I see the patient on recall appointment I mention their miracle mix filling(s) and ask if they are ready to have a crown. Eventually they go ahead and have a crown done since it is more ideal for their tooth and will help protect it from fracture.