The flow of a cursive shorthand system is unmatched by anything else. I highly recommend learning enougnh to experience it.
(The drawback with more phonetic systems like Gregg is that one has to learn entirely new ways of spelling words. But normal English spelling is so complicated that tradeoff can be worth it for heavy usage. Orthographic systems often also contain phonetic components, but they tend to be optional extensions that improve efficiency, rather than required like with purely phonetic systems.)