LLVM is a square peg. If your project needs a square shaped peg then it will do amazing things for you. On the other hand if you want it to do circle shaped things you will feel the pain.
Thanks for the fortune-cookie wisdom. That tells no one anything. We don't have square pegs or round holes, we have complex engineering problems to solve, and LLVM's complex shape is obscured by a community that doesn't agree on its shape, so we have no way to tell if it fits our holes.