I have high mount exhaust; the problem with most soft luggage is that it fouls high-mounts, and heat shield or no, you will have a failure if the luggage contacts the pipe for a prolonged period.
I found these:
http://www.revpack.com/motorcycle/pr.../TourPack.html a couple of years ago: they are built great, they won't foul your pipe, they stay on without shifting, and they don't leak in anything but the worst extended downpours (for which I have the waterproof covers.
Highly Recommend.