I have feelings you know. The problem now is what part of me has the feelings!
Yes they have the largest Autosomal DNA testing, which will go back about 6 generations acutely. I have read that there is 3 types of testing; autosomal (atDNA) testing, mitochondrial (mtDNA) and Y-chromosome (Y-DNA) testing.
This is what I have just read;
Which Type of DNA Testing is the Most Accurate?
Both mtDNA testing and Y-DNA testing are more accurate than autosomal tests if you want to learn about distant ancestors. Because autosomal tests reveal such a variety of genetic activity from every branch of your family tree, they are less accurate across multiple generations. Although anyone with whom you share genetic material is related to you somehow, atDNA tests aren’t recommended beyond six generations at the most.
In contrast, mitochondrial tests and Y-chromosome tests can be extremely accurate across dozens of generations. It’s like the difference between shining a narrow beam of light instead of allowing that same light to shine across a wider area. A narrow beam of light will stretch further into the distance, but a wider beam will light up more ground around you.
Scientists have traced mitochondrial DNA all the way back to a woman referred to as ‘mitochondrial Eve,’ who is believed to have lived around 200,000 years ago, which shows the accuracy of mtDNA tests. ‘Eve’ is the most recent common female ancestor for everyone alive today.
That means that every human being on the planet shares the DNA of this single woman, not that she was the first human woman, ever. She was just the most recent woman whose female line continued unbroken until today.
Similarly, scientists were able to use Y-DNA tests to identify ‘chromosomal Adam’ as the most recent common male ancestor of all humanity (but again, not the first human man). Scientists have placed him as having lived around 100,000 years ago, which isn’t at the same time as mitochondrial Eve, but they do have theories to explain that, including the frequency of polygamy.
Source;
https://www.top10bestdnatesting.com/articles/scientific-difference-between-dna-tests
That all said and after seeing the prices I think I only need to go back 6 generations, it's £40 cheaper than the competition. So
www.ancestry.co.uk it is then.