vim supertab, toward a best way to insert a tab

I really like the supertab plugin. Reaching <C-x><C-p> is a bit too long and mapping it to tab gives me a better workflow. However, sometime I just want to insert a regular tab and for this I need to insert a space first, i.e. foo<Space><Tab>bar.

This pollute my sources with useless spaces before each tab char (this assuming I don't use expandtab).

I am wondering is there is a smarter way to use auto-completion ?

1. Going back to <C-x><C-p> which is much slower
2. Using another key mapping like
3. Using supertab with a wiser feature: i. Automatically insert a <Tab> if I press a char that doesn't match any of the possible completions. ii. Inserting a real tab with
4. ???

Any ideas?

You can suppress the Supertab trigger and insert a literal tab by pressing <C-v><Tab>. (On Windows, that frequently is <C-q><Tab>.)

Supertab also provides a mapping for direct input, by default <C-Tab>; see :help supertab-mappingtabliteral. That default key combination probably only works in GVIM, though.