I can't answer your questions about the DW4200 because I have no experience with it. I had the DW4000 system for about 5 years and had some bad service, and some really good service with it. The last couple of months before I upgraded, my speeds were very low. I did some research to find that the popular opinion is that Hughes is doing a lot of load balancing, and in turn caused the load on the bird and transponder I was on to be very high. I also feel it's only a matter of time before Hughes phases out the service for DW3000 &4000 customers. (I actually got this from a Tier4 tech support guy).
As far as tweaks, I used DRTCP, which you can download from http://www.dslreports.com/drtcp
Antother good forum to go to learn about Hughesnet Satellite is http:/www.dslreports.com/forum/sat They have a world of info about all the systems Hughes has. They have a section called Satellite FAQ - Tweaks and Tips that is very helpful. http://www.dslreports.com/faq/satellite Hope this helps.