I've been to Destihl a few times and always leave unsatisfied. As a disclaimer I have only gone as a member of a big group. Also, they have always been very good about steering me away from unsafe gluten-y dishes and I've never gotten sick.
However, the actual food is lacking. I had dijon chicken the last time I was there and it was burnt and over cooked but the sides were underdone. My boyfriend got a steak which came out a bit too rare and was just a bad cut- riddled with lines of fat. On a previous visit I had fish dish that was so over-seasoned with peppercorn I could hardly eat it.
I know several people who swear by their food but it seems to be inconsistent at best.