Todd, before you buy from Light Impressions do a search here and on the large format forum. They aren't the reputable company they once were. But they do seem to have moved back to Rochester, NY so maybe things have changed again for the better.
I just tried out Frame Destination, who are sponsors here, and I was very happy with the experience. I ordered frames, mat board and plexi and it was the best packing job I have seen. Plus the cuts are clean on the metal frames and the plexi had not dust or other cutting debris on it. All much better than the other place I used.