Many English expressions are constituted of a verb with a preposition (from, to, etc.). Let's take to benefit from as an example:
The customer benefits from a service.
Say I now want to refer to the service itself. I have often seen the following sentence structure:
[It is] the service that the customer benefits from.
However, I believe I have once learned that — despite being commonly used — it is not proper English to put the preposition (here “from”) at the end of the sentence. (Correct me if I'm wrong.)
So I would like to know what would be the proper way to refer to “service” in this case? Is the following proposal correct (it sound quite “bulky” to me):
[It is] the service from which the customer benefits.
If not, what would be the correct way to write the sentence in a formal context?