VWP authorization approved after U.S. vusa refusal

Hi,

I would like some information.

I applied for a U.S. visa at the U.S. Embassy in London in 2009 (I applied on Russian passport, before becoming UK Citizen) and I was found ineligible for non immigrant visa under Section 214(b) of the Immigration and Nationality Act.
Now I am a UK Citizen and I would like to go to the USA for a holiday. As a UK Citizen I am eligible to travel to the United States visa free under the Visa Waiver Program. I applied for it on http://www.cbp.gov/ and my travel authorization was approved.
I know that travelers who have been refused a visa under the provisions of Section 221(g) or 214(b) of the Immigration and Nationality Act are not prohibited from traveling visa free under the Visa Waiver Program. However, they will be questioned by an immigration official at the U. S. port of entry regarding the refusal by the Embassy or Consulate.
What I would like to know:
Has anyone been in the same situation? Did you manage to go through Immigration without any problem?
What kind of questions did they ask?

Many thanks in advance for your help!

You might wait a while for an answer as the US forum (where I moved your post to as it is not relevant in the Tier 1 forum where you posted it), is not very busy, if I can use that word.