I tested with Ancestry first and then tried 23andme. I have over 1200 "matches" on Ancestry with no tree hints. I only have four matches with 96% confidence and even with the extensive trees that we all have, no matches have been found. Add to that my confusing ethnicity of 90% British Isles/10% Persian/Turkish - all members of my family are from Germany-speaking countries immigrating to US between 1818 and 1850.
23andme has a more balanced breakdown of my ethnicity; mostly Northern European. I also learned of a previously unknown 2% Ashkenazi which makes the blank spots in my tree all the more interesting.
I have had more matching names on 23andme. I have 650 matches and my sister and brother both have over 950 each. I like working with the raw data and am compiling a list of the people who are sharing with me based on each chromosome match - eventually it could lead to a common ancestor.
I'm very happy with my 23andme results and am hoping that I'll get more results/clarity from Ancestry.com in the future.
Enjoy!