Just out of curiosity, if you were to buy a permanent PR6, how much would you expect to pay? Also, what about a permanent PR5, PR6, PR7 and PR8, what would you expect to pay for those links?
I think you go to really know just how "permanent" the link will be. If the link gets pulled down after a couple of months then it isn't going to be worth that much.
No guarantee to PR's and getting one or two backlinks from PR6 don't do much difference to your site SERP's.
It all depends. Anymore it seems like google weighs more heavily to those links of relevance than the high PR links.
it depends on several factors man.. the topic of the site, and the # of outbound links.. if you have 50+ outbound links.. I'd say a prem pr6 is work about 5$