ahh the good old dunlops SP20FE's I couldn't believe it myself when these were on par agaist the potenzas RE92's! The magic is just more air, my tire accident was from pumping really high pressure (which i won't tell you because iam extremely sick of all the flames believe me...) and I ran over something? I heard plastic that's all, and by the time I got home I heard this hissing sound... so if I had low pressure to begin with... it could have gone boom sooner!
But lucky the tire flatted itself out, got it fixed and now I'm back on the road! But now the pressure is not as high just because, I dunno I don't trust this fixed tire, maybe when I get four new dunlops I"ll make high pressure a top priority. Until then want more roll, more air that's for sure! Keep increasing until you get a level that you feel comfortable with, that's the best advice I can give you.
As for me I'm down back to sidewall, I used to have it 15% over but now that tire accident just shows these tires are aging (still on the same set!). Now I don't know if a tire with less air would be more immune to puncture or more likely to do so in my situation even though I do not get to see what really I ran over (when going over that same road that it happened, all I see is this tiny ... i don't even know what it is! but it is part of the street that's for sure) but one thing for sure, the extra air in the tires allowed me to get home safely before I realized what really happened to my tires. By I getting out of my car and hearing the hissing the first thing I did was "Oh no its going to blow! High tire pressure!! (Yes i've seen this with my eyes happened being a passenger in a friend's car)" but an hour later reveals air just leaked out, air that allowed me to get home!!!
So right now about high tire pressure, I honestly don't know what I believe. You got 90% of the population saying overinflation blah blah and you got this 10% saying overinflation is awesome. And where I lie well, I'm still deciding, but you can't decide if you don't try for yourself
edit: now that i've given them one more thought, maybe dunlops FE20 really do suck, could be just the tire