It is hard to say which is worth it. We must first understand one thing, what we buy from patents is only "rights", not technology. Some real technical details may not be written in the patent specification, so there is still an essential difference between patent and technology, and patent is a right.
From the time limit, it may be faster to buy a patent, and it may be slower to review the application for self-development. Whether to buy or develop it yourself should be judged comprehensively.