solos are are great!!!
But got to remember lots of solo ad sellers selling dud lists, that have been spammed too 1 gazillion times.
It does take some testing, but have made thousands online, by doing solos, and renting out lists, or doing JV with businesses with large databases 500K +
plus if you are doing solo ads consistently, and do not have a GOOD FUNNEL in place and a back end marketing system, you are basically wasting precious money and time and resources as well.
so I agree, solo ads are a very good way to earn FAST coin, but you have to work hard and test as you say.
Again, I hate the people that say EMAIL MARKETING does not work, its basically the foundations for companies doing MILLIONS of dollars online fast.
I remember JOHN REESE making $1,000,000 USD though affiliates and EMAIL MARKETING many years ago. IT was the first or second time, it was ever done, and proof of how powerful this sort of technique is. What he didnt say is the months and months of hard work, and how it nearly cost him his health!!