As I stated above, the worst DSR anybody could have left for you is 3. And it's most likely a few 4s.

Even if I knew who did it (and I do on a few), I wouldn't block them for leaving a 4.

Don't expect too much repeat business (the best kind) if you start doing that. And 5s across the board are almost impossible to achieve, much less sustain. It's all well and good to aspire to blanket 5s, but at some point reality needs to set in.

You can't please all the people all the time.