Would the fact that my PS3 is less than a year old make a difference. Maybe I just got lucky with PS3 speeds since I know a lot of people who complain over theirs.
I'd take the slower Vita speeds if it means I have faster PS3 speeds that average. It's much easier to download and transfer games via the PS3 since it's faster, appears to have a better install success rate. But more importantly I can download while playing.
Both Uncharted and Gravity Rush disable my WiFi
It's a combination of ISP, router settings, file system, server load, and local network congestion issues. Any one of these can affect a setup.