Complex sentence: They hold great appeal since time is often a critical factor in the success with which a motorsports injury can be treated; however, they are costly to build, costlier yet to staff regularly, and are not seen at most facilities.
Split into simpler sentences: They hold great appeal since time is often a critical factor in the success with which a motorsports injury can be treated. However, they are costly to build, costlier yet to staff regularly, and are not seen at most facilities.