Lately I've been writing a lot of LaTeX rather than programming. Nvi has macros, mappings, and abbreviations so it's not hard to deal with verbosity. In the past, I've written in languages like python, Haskell, SQL, R, and even HTML. It's never been a problem. I've never had to write Java though, so maybe I'd use something else if I were forced to.
Code completion, like syntax highlighting, seems to be one of those tools that changes how you think and I'm not sure it's for the better. Being able to quickly bang out a bunch of glue code may be great for a 9-5 but I think it gets in the way of the creative process. That's just my opinion, though. I'm not aware of any research into this idea.
I personally have never used code completion, though I don't think it's affected me much as a C, Python and Lisp programmer. I wouldn't want to try Java without an IDE, though (I use Emacs).
Code completion, like syntax highlighting, seems to be one of those tools that changes how you think and I'm not sure it's for the better. Being able to quickly bang out a bunch of glue code may be great for a 9-5 but I think it gets in the way of the creative process. That's just my opinion, though. I'm not aware of any research into this idea.