I went the year it was 105 - we had no trouble parking but a friend of mine came from Portland by bus. I think if I were to do it again - that is what I would do - look for a bus in and out. We did arrive early. And I would also take food with me. They are right, the restaurants are busy because it is a small town and for some reason do no bring in food trucks. (Or at least they did not the year I attended.)
There are over 1000 quilts hung from first and second story railings - so you might want to bring some small binoculars too. I thought it was well worth it - we stayed in a nice hotel in Bend and made a big weekend of it. (The show is only one day.)