We have just started working with WebDistricts, and so far, the experience has been positive. They are very responsive and do quick revisions.
If you know what you want, they will execute it well.
Cons: Unfortunately, they don't have a dedicated in-house web designer, only web devs; therefore, submitted designs require a lot of work and a lot of back and forth.
Recommendation: They should take more time to work through the design, site map, and content before submitting it. Strive to be professional over fast.