I recently signed up and had an account with Tradedoubler, but I deleted the account a month later. The whole site is poorly organized despite the high profile companies that they have on their books. What I realize is most companies have a couple of links with different companies, so you need to choose the best one.
Tradedoubler were fairly unprofessional, and I was accepted on one program but the links didn't work, the banners were old, and trying to navigate the site to create a link too so long it didn't seem worth it.
I was then rejected for three programs, but I was slightly suspicious as manual approval usually comes from the company, but this comes from the account manager of the program. I had all three rejected at 8.30 p.m. and this is a UK based company.
I then got an email from the account manager of the program I was on saying the site was being upgraded and I needed to remove all links and banners for 11 days and then add them all again. There was no way I was going to put them all back, so I deleted my account. Their wording and communications are unprofessionally worded, and that to me was a sign of a poorly run business.