Are bidding directories safe to use ?

[megaman]

I've seen a lot of directories which are based on the concept of bidding. Are these sites pretty much illegal according to google's paid link policies. I mean the whole concept of bidding doesn't really tie in anywhere with the concept of a review fee.

I've seen some really good bidding directories with loads of backlinks and good PR, but are these likely to hurt my SERP's if I link n them... Would love to hear what other's have experienced with Bid directories.

I may even consider starting one up if they earn decent money!

[cookiemonster]

I've used them on some of my poker and gambling sites, and they do indeed pass link juice but they are risky.... so wouldn't really invest too much. Ultimately unless the bid dir is using nofollow it will be penalised eventually.