With the DNA, I think you get out of it what you put into it. If you only look at your nationality estimate, then you will find the experience wholly unsatisfying. If you look at how many people haven't connected their trees then you might not see the point. If you do all the work yourself, rummaging through the profiles and contacting people, you might get something out of it. Ancestry doesn't make it easy for you to make use of the DNA section, you have to get deeply involved.
I am the researcher behind my mother's DNA results on Ancestry. I process them and see if I can work out how they are related. I have currently identified the link of 47 profiles- the more I can identify, the more I can work out using "Shared Matches". For a lot of those profiles they are connected to me around a few central hubs, such as my UGLOW line, TREWARTHA line or my WOOD line- this just about confirms the paperwork of those lines as correct, which is good to know because of the potential for incorrect research, non-paternal events etc. Others have helped in other ways- for example, my 2xgt grandmother was illegitimate and we had a theory about who the father was. After receiving multiple different DNA matches from the supposed father's family we can only conclude that the father himself was one of four, perhaps five, different men from that family. We might never know which one, but his ancestry is right there to see.
While I wasn't the one who spent the money on it, I certainly intend of making use of every penny of it.
Ayashi