tsearch2: plainto_tsquery() with OR?

I have some questions related to tsearch2:

1) Is
...WHERE rank(myTsVector, myTsQuery) > 0 ...
just as fast as
...WHERE myTsVector @@ myTsQuery...
?

2)) I will use plainto_tsquery() to parse search keys entered by a
website user to a tsquery. However, if only some of the entered keywords
does not exist in the searched tsvectors (but others do), I would still
like the search result to be "true".
plainto_tsquery() glues each keyword together with "&". I search for a
plainto_tsquery() that glues the keywords with an "|" (the OR operator).
In that way, not ALL keywords are required to exist in the tsvector in
order for the row to be returned,