I keep getting this one connection error(8013013D), even after opening up the ports and following at least one or two walkthroughs on how to set up a more stable connection.
My wireless signal is usually somewhere in the range of 67-80% and my router is downstairs.
I just look at it as a temporary hiccup, since most times I'm able to just sign right back into PSN and I'm fine from then on out. Of course, if I had access to a drill and didn't mind making a hole in my wall downstairs where my router is and upstairs in my floor behind my tv, I'd set up for wired from the router since I would prefer the more stable signal.
But for what I use the PS3 for now online, the connection is good enough.