I have the 38" fairing on my Yakima bars. It is the exact same width as the rails, so it looks pretty perfect. That said, your bars stick out past the fairing on either side quite a bit still. (I have 48" bars). You could probably use the 44" fairing, but the bottom edge of the fairing would start to hang out in open space at the ends, due the roof not being quite that wide.
I like my 38".