The only real way to test is to have the site respond to at least hundreds of page requests in a short period. There are services and scripts for that but I don’t have one handy for you now, sorry. Posting just a single result with and a single one without the caching can be very misleading.
Back in 2010 was a comprehensive WP cache comparison (Google cache) was done with 1,000 requests at 10 concurrent and the summary said “Overall the best out of the box cache plugin configuration in my opinion is: Hyper Cache + DB Cache Reloaded”.
Without caching the server was able to answer to 13.96 requests per second while spending 716.580 ms per request (mean average). With DB Cache Reloaded the numbers were 15.04 per second and 665.09 ms per request; 8 % faster.
The old numbers might or might not apply, but they are in line with my gut feeling based on a small sample: DBCRF has a slight positive effect on WP speed. The best part is that it can be used with Hyper Cache (Extended) to benefit from both.