> Why did nobody use it before the Raptor? It’s not the best choice for an high-budget high-performance expendable multi-stage rocket. Using kerolox/SRBs in t

> Why did nobody use it before the Raptor? It’s not the best choice for an high-budget high-performance expendable multi-stage rocket. Using kerolox/SRBs in the first stage and hydrolox in the second stage gives better overall performance. Metholox is better for re-use, using the same engine in multiple stages lowers costs and complexity, and you can produce the fuel on Mars.