In some other threads there have been discussions about how well various DNA tests met people's expectations. There are several types of tests, and several companies that offer them. Which test and company are the best depends, IMO, on what a person's testing goals are. I thought I would share my experience and see what others might offer in the hope that people who are considering testing can make informed choices.
When I started DNA testing my goal was to confirm my father's family's place of origin. I had a good paper trail, but a couple of troubling inconsistencies that I hoped to resolve through DNA. I started with a YDNA (paternal ancestry) test from Family Tree DNA. I chose that company because it offered a more comprehensive test than Ancestry did, and because there was a surname project group related to my family that I could join.
This proved to be a good start. I obtained several matches to people who shared my father's surname and whose families were in the same general area, including one close match whose ancestors lived about 10 miles from my father's family's presumed home. This was consistent with my research, but not yet proof.
(An aside--at this point I began to get very interested in DNA and deep ancestry and so did a "deep clade" test with FTDNA and the National Geographic Geno 2.0 test. But that's another story!)
In order to get more information, I ordered the autosomal test from FTDNA and the Ancestry test. My goal was to find other people who are related to my father's family and thus try to resolve the inconsistencies in the paper record. I was successful. I found a 4th cousin through Ancestry who was related to my 2xGGM, and that confirmed that I had found the right person and location.
As a result of the autosomal tests, I also made contact with a person who lived in my family's homeland and who was expert in the local records. When he had his father do an autosomal test with FTDNA we turned out to be related, which resolved my other uncertainty regarding my father's place of origin.
So, meeting my original goal required a combination of two types of test (YDNA and autosomal), with two different companies (FTDNA and Ancestry).
My current goal is to get past a couple of brick walls in my mother's family. I am currently analyzing my autosomal results for that purpose and am awaiting results from a third company, 23 and Me, to expand the pool of possible matches. I also plan to do mitochondrial (maternal) DNA testing through FTDNA in the coming months.
I got some bonuses along the way--several previously unknown cousins, and insight into my deep ancestry and a new interest in DNA. The bottom line, however, is that to pursue my goals requires several types of tests and that, at present, no single company provides both the tests and the tools to fully meet them.
Other's experiences would be most helpful.