Improving NTSC on DirecTV

I have an Elite 510 RPTV and have been putting off buying the HD satellite receiver until there is more content, but the blocky picture is really annoying. If I buy one, will I at least get some improvement in non-HD DirecTV signals simply from switching from S-video output to component? Any other ideas on mitigating the "blockiness"?
I just went from a older sony direct TV (sat 60 I think) reciever to the HDSAT100. The HDTV images are amazing. The super bowl was really cool. However, I could never really watch normal TV before the hdsat 100. It really helps normal sat images. Not sure if it's the component or the sat100 upconverting everthing it can. I use a sony vplvw10ht for a projector.

It's worth it from my experience...
I switched from c-band satellite to Directv over a year ago using the RCA DTC-100. The HDTV picture was great, but the only channels carrying HDTV were 509 (HBO), and 199 (demo loop). There may be more now.
The rest of the channels were "fuzzy" looking even when scan doubled. I have an Electrohome 8500 projector and 100" 4:3 screen. I would guess the resolution to be around 300 where normal NTSC would be 540.
I switched back to c-band when my contract was up. I hope Directv has plans to upgrade their signal when the merger with Dish network is completed. I like the ease of tuning and lack of maintenance, but don't care for the reception!