Good, I suppose, for launches of small hardened payloads from a small footprint. You would get away from most of the atmospheric issues by building on top of a mountain as with major telescopes.
Not sure using kinetic energy as a storage mechanism is better than capacitors once overcoming friction is taken into account.
Linear mass drivers using maglev stretching over many kilometres and finishing by climbing up mountains have long been considered as they would allow slower accelerations suitable for other loads, including people.