I am a US citizen with a DUI from 9 years ago, who just applied for a tourist visa at the China Consulate in Los Angeles. I was approved. I have read a lot of posts in forums about what people think others should do - Since I can only speak to my experience, I'd like to give insight on how I handled my Visa application to help those make their decisions on whether to divulge info on their DUI or not.
After reading posts about coming forthright OR not on your form, I printed both versions in preparation for my application to make a last minute call. Once I got to the consulate, I decided to use the form where I was honest about my DUI as I didn't feel right lying.
Below is basically what I put in section 3.6 where they ask you to give details about any criminal records in any country:
Month YEAR - UNITED STATES
Misdemeanor - DUI Vehicle Code 23152(a)
[Short explanation] - I have completed all the required programs, AA meetings and probations. Have since separated drinking and driving entirely. I intend to comply with all Chinese laws and be respectful to the cultures and citizens of the country.
Did I take the advice of many to have a VERY detailed itinerary, (even added a lodging breakdown), ALL of my hotel confirmations and activities ready to ensure a better chance of my application approval? Yes, but they only took confirmations for my inbound/outbound flights to China and the incoming's city's hotel confirmation along with the app, photo and passport copy.
Them not taking my itinerary left me worried up until I paid for my application and saw that I was approved.
Should you be forthright about your past DUI(s)? Idk, that's up to you but I hope this helps ease some of your minds IF you decide to put it on your application - it still is not a guarantee you can get approved by being honest but it can be done. I also want to note that I did not use an agency to help me. If you are thorough, you will be fine but if you lack attention to detail, perhaps an agency may be helpful.