Solo ads are a very reliable Pay Per Click traffic platform when purchased from honest and trustworthy vendors. The traffic is generated from a solo ad vendors list (eMail) and not from search engines. Even better you only pay when someone clicks on an eMail link and arrives at your chosen URL.
Solo Ads are used by top marketers who are looking to get fast surges of traffic to their offers immediately.
The benefit of Solo Ads is that it is the best, highly targeted form of advertising. This is because you are able to target people who are very interested in your offers. It is very scalable as you get to choose how many Tier 1 visitors you want to see your offers.