I don't like vertical seams on my longarm set-up, as they will create uneven and baggy areas when rolling up. But this is OK if I can put the quilt up side ways. Also I wouldn't cut the 9" off before quilting 'cause you just may end up with a 12" strip after, ( you will have that extra 3" all around to trim that won't be quilted). Hope that's a bit clearer than mud