We looked at the Grand Design and for the most part we liked it. The 40' model which is the 385 I believe. The main thing we didn't like about it was the bedroom and the bathroom. There is only one entrance to the bathroom and the bed was a slide out. That was a deal killer for me and the wife. But other than that it seemed to be a great looking unit.
I believe the Grand Design was started up by the guys who started Keystone. The one thing we did like about it was the overhead storage on the galley slide. Not too many have those.
I would take opinions from these forums and just put them in the bank, I wouldn't make a decision on what other people think. Because what is great for me my not be great for you. It is all going to be preference of layout and options. As far as quality goes if you search the web as I did for the last 15 months, you will see dis-satisfied customers for every RV builder. Take all those with a grain of salt as well. I am very confident that there are more satisfied customers then non-satisfied. You only really hear the bad and rarely hear the good.
Good luck with your search, It was a fun adventure.