I, too had to do battle with Asset Acceptance and for years they kept verifying the debt. However, I followed the advice I read here and filed the online complaint on Sept 10th. I received an email response from BBB with Asset Acceptance agreeing to delete on the 13th and so far I can confirm that Experian deleted on the 17th and Equifax as of yesterday. Still waiting for TransUnion. 
I have two small collections left (totaling under $700) and i hope my score will increase. Asset's was fr $1,900 so my fingers are crossed!
Good luck to you!
Starting Score: 600's