There has been a lot of talk about Alexa for a long time. Some people are still under the false impression that the Alexa numbers are accurate and reliable. Some aren't aware of how easy it is to manipulate the numbers and that there are people who do manipulate them.
Certain people and even people in some countries are much more likely to have the Alexa toolbar installed. This helps to give misleading information.
5 Star might be popular, but according to Alexa, 5 Star ranks better than some major United States metropolitan newspaper and television sites. That simply isn't correct. It is a result of the type of people who are likely to have the Alexa Toolbar installed and the sites they are more likely to visit. Those newspaper and television sites have more visitors from the general population who are a lot less likely to have and Alexa Toolbar or even know what it is.
There are other choices besides Alexa and some of them probably also have faults. Some get a little attention and some get very little attention.
One that people might not hear a lot about is Compete. In many cases the information supplied by Compete varies greatly from what Alexa shows. In some cases the two are close to each other. Compete might have some of the same faults as Alexa.
But both Compete and Alexa can help give you some information that could be helpful. You might like Compete more than Alexa, you might like Alexa more or you might not like either of them.
With compete you can get what they call a "SnapShot" of a site by typing in the URL of the site. With the SnapShot you may obtain the estimated unique visitors in a month, the rank, how many pages the average person views on each visit and how long the average visitors stays.
Comparisons of different periods of time are available. It also indicates when a site shows no evidence of malicious intent.
Here is a link to Compete in case you want to give it a try by checking a few sites
Compete