Since I "grew up" without BASH and the benifits of
"auto-complete", I don't use it when using bash.
However, ksh fully supports history and using your
favorite editor (vi or emacs) for the command line
interface and browsing through your command history...
# from .profile file
export HISTSIZE=100
export EDITOR=vi
...give me a history of my last 100 commands (lines)
and allows me to use a vi like interface. For instance,
I ran a telnet command earlier with an IP address.
I want to get to that system again.
At the command line I press Esc then /telnet
and it will search ("/") my history for "telnet".
If I ran several telnets an I don't get the one in question
then I type /Enter and it searches again.
That's just one example.
I don't know (but I have heard rumors) that auto-complete
is available on ksh now but I cannot verify or deny this