Exchanging links with higher PR sites

Many many PR(x)s for a PR(x + 1)?

[Rollo]

I'm going about getting some PR7s at the moment and I was interested in hearing your opinions about how many PR6's one should trade for a PR7?

How about # of 5's for a 6? # of 7's for an 8, etc.

Thanks, Rollo

[GranPops]

The three most important aspects of SEO, since March, are IMHO
1. Anchor text
2. Anchor text different from point 1
3. Anchor text different from points 1 and 2

However, PR is of value for trading with webmasters who don't accept the above.

Assuming the same No. of links per page, both internal and external, which is as rare as teddy bear poo, our assumption is somewhere between 7 and 10.

We have a prog, for fun, that actually does the calcs with variables of PR, no. of links, and log assumption.

From the G docs on the subject, which of the following would you prefer to trade with?

A PR1 with a single outgoing link, or a PR3 with 99 internal links and 1 outgoing?

A PR3 with 1 outgoing link or a PR5 with 99 internal links and 1 outgoing?

A PR2 with 1 link, or a PR5 with 250 internal or outgoing?

A PR5 with 1, or a PR7 with 100 internal or outgoing?

Answers on a postcard please LOL