I really like the manga, though the inconsistent art due to different arcs having different artists can be annoying, but most are really good.
Unfortunately only the spin-off 'The Honor Student at Magic High' has an official English release, with ten volumes released and the focus shifted to Miyuki and the girls rather than Tatsuya.
That said, there are fan-translations of many arcs for most of the early arcs, but so far only the arcs for Volumes 1-6, 8 and 9 are completely translated into English so if you can't read Japanese you won't be able to read beyond where the anime will end, though you can read Volumes 5 and 8 which were skipped by the anime.
So in summery, they are good manga series and worth a read and full of skipped content, but they are incomplete and you will likely be waiting a while for them to catch up to the Japanese releases so if you want all the details the Light Novels may be the better choice.