Do you mean best as in, what is the most precise way for you to measure performance without an FCAT machine? If you want to go down that road, I'll give you all the excel equations you need to deduce frame time numbers.
No the latter but this is good to know as well.
If you just want to see how badass your PC is, run 3DMark Firestrike.
*EDIT* Just going to include them anyway in case.
Get fraps. Click the option that allows you to run frame times. From there, you can use
frafs Bench Viewer, or dump the data into Excel. Generally you want to keep the benchmark to under a minute, and make sure it's easily repeatable. Do it at least 6 times.
Now you can view those files with frafs, or if you prefer to dump it into excel, average out the data.
The formula for 99th Percentile is
How to view frames over a given amount, you use
You can swap out that 16.7 with any other time you might be interested in.
**EDIT 2***
I almost forgot, it doesn't spit out the frame times, it just stamps at what time each frame was created. So for each line, you need to use an equation that does simple subtraction. Here's a screenshot for an example:
Column C uses that subtraction formula for each line. You can just copy/pasta it and excel works its magic. I think.