Views versus user-defined functions: formatting, comments, performance, etc.

Hi:

I notice when I save a view, I lose all the formatting and comments.
As I was writing a complicated view, wanting to retain the format and
comments, I thought I could just save it as a function that returns a
table value.  A function would evaluate to the same value as a view,
but changing it later might be less confusing.

However, I'm guessing (since I don't know anything about the
internals) that the loss of formatting and comments is a result of the
view being processed and stored in a more computer-friendly format,
while functions are simply stored as the text that I type.  That gives
me reason to suspect there may be performance or other differences
between the same SQL statement stored either as a view or a
user-defined function.

So that's my question: as someone who doesn't have a problem with
putting a pair of empty parentheses at the end of a table variable
name, what factors should I be thinking of while deciding whether to
store my self-composed, multi-hundred-line long SQL statement as a
view or a function?

--
Adam Mackler