I took a newly completed quilt top to my LQS today for a show & tell and the owner nicely pointed out that 3 of my blocks were turned sideways (I had already mentioned that I'd had to rip one out and turn it -- it was easy to mis-turn a block in the design). Although I groaned (nobody is happy about frogging) I was very glad to have been told, since it hadn't been quilted yet. So I came home and spent a couple of hours ripping and resewing. But I'm happier.
So yes, if it's not yet quilted I would want to know.