They are good, but id just advise people to bare in mind that they are far from being correct and up to date from my experience...
My first experience was a car that i knew had been a previous Finance repo, finance was cleared by the garage and sold to a guy who after 1 year i bought it from, when i did the check it still was down as finance owed, so i got onto them and 2 days later got an email back that they had contacted the Finace agency and it was actually clear and that they hadnt up dated the info... ffs after nearly 2 yrs i asked.. and i sold the car 1 year after that and it was still listed as finance owed when it was clear...
My 2nd experience as a mileage issue, rang them and told them the mileage that was on the car and it come up as wrong and i got the something like the following.. for example in 2007 it had 60k miles, 2008 70k miles 2009 80k miles 2010 90k miles 2011 70k miles and now has 95k miles.. which was only a few months after the supposedly 70k reading... so 25 k miles mysteriously up on car in few months... i qiestioned the guy on phone and he said it couldnt be right aswell... what had happend? some goon in Nct instead of writing down in Miles what was on the car read it as Kms... so for talk sake 100k miles becomes when mistaken as KMS 60k miles..
So just be carefull and dont go by it 100% as ive come across 2 mistakes that would have stopped someone else buying to perfectly legit cars