Write! have written a thriller and have acquaintances who love to read that genre, you’ve found the perfect audience. Don’t ask them what’s wrong or how to fix it, just get their reactions to what they read. Did the opening grab them? Was there any point at which they would have stopped reading if it hadn’t been written by someone they know? How did they feel about the characters? Which ones did they find most interesting, which least interesting? The danger that comes with getting comments from other writers is that often they start telling you how they would have.