Unfortunately, grow traffic proved out like I suspected. It is not, at least not obviously, a scam. It is, however, useless for most purposes.
I purchased 10k visits over 10 days for 28 dollars. These were directed to a landing page that offers a discount code in exchange for an email signup. My results ended up being:
- 4756 hits to my landing page (not sure why it didn’t register 10,000 but whatever
- 0 email addresses received
Based on that confidence interval calculator I posted a few weeks ago that puts the conversion rate between 0 and 0.1%. A very similar landing page linked to google ads got 12 out of 100 visitors to give their emails, which gives us 6.6-19.1% conversion.
Conclusion: don’t waste your money. So far facebook ads work the best, but are also the most difficult to do right.