This is exactly why Google are changing their algorythms.
To stop people manipulating and cheating their way into search results.
Look at it this way (and it's been said before) We all
SEO our pages and think they should be higher than they really are because of the great content or whatever. We're all biased and believe our sites are great.
If this was the case, more people would link to your site because of great content and you would receive a higher
PR naturally.
Manipulation of the system is not the way to go. Google will simply adapt and penalise the cheaters and the cheaters will be left out of pocket.
In my opinion, stay away from anyone that offers you ways of getting a higher
PR.
The only REAL way to increase
PR and get better placement in the engines is by good old fashioned elbow grease.
Trust me, those who seek and work to get good links to their sites will reap the benefits for years to come.