OK, lets see if I can post the screenshots...
1) Downloading from K2S via JD (link grabbed from planetsuzy forum using right-click/"Download Link with JDownloader"). This is 30Kbps.
2) Downlading from K2S via browser, clicked-through via Planetsuzy. This is 150Kbps.
3) Comparison with the 30Kbps K2S file AND a depositfile link (downloading at 200Kbps) plus a Rapidgator link (downloading at 50Kbps), all via JD, to show it's not a bandwidth issue with my connection
4) Fileboom link in browser when the link is opened in browser from JD (right-click "open in browser"). Note the "Speed Max = 30 kbps" shown. That's because the link doesn't contain any referrer data. You'd get the same if the link was simply pasted into the browser via copy/paste.
5) Fileboom link (the same one as above) if clicked through via Planetsuzy (so it contains referrer data)
This is due to a negotiated speed rate between Planetsuzy and Moneyplatform (the parent of Keep2share, Fileboom, and TezFiles, all which behave identically) in order to get "preferred" hoster status. That means files clicked through Planetsuzy get faster download speeds than grabbing the same links from other sources. In my case I'm grabbing them from Planetsuzy, but queuing them in JD a dozen at a time.
Filejoker appears to have the same kind of agreement, although it also affects wait time between downloads.
Note that I am not using ANY logins for any of the downloads- it's all done as an anonymous user.