fun with mrtg graphs...
I have to go with lenny2 again here... that webair explanation is exactly the one used by hosts that cahrge 95th - there is a reason for that.
rarely do customers have a nice flat traffic attern to make 95th feasible.
Here's a few mrtg graphs:
client 1:
http://ezprovider.net/week1.png
http://ezprovider.net/month1.png
client 2:
http://ezprovider.net/week2.png
http://ezprovider.net/month2.png
client 3:
http://ezprovider.net/week3.png
http://ezprovider.net/month3.png
None of these clients would benefit from 95th... (ps - the cliets are japanese, thus the spikes at the early hours of the day)