Entirely depends on the individual. With a virtual on-screen keyboard, I can rarely type even one word without error. It's like my fingertips are just too big to hit the keys accurately. Swipe-keying is somewhat better/faster but I'm much better with real physical keys. Speech-to-text used to be pretty bad but with my current phone it's better than typing, for me. The downside is I hate talking to computers.

Have you used SwiftKey? I find it corrects 99% of my errors, to the point where I just press keys in the vicinity of what I want to type and it comes out correct.