As a friend of mine is a seasoned rider/racer; he has suggested that I could drop the pressure from 42psi to maybe 34 front and 36 rear.
Different riders tend to have different opinions on air pressure based on variables important to each of those riders. Air pressure directly affects the profile of the tire which affects handling characteristics within the limitations of the tire as well the aforementioned variables.
First you should probably have your rider/racer friend explain why he thinks you and your ST should run his recommended pressures - pros and con.
Second if you try his recommendations see if you can feel the pros he states and avoid the cons.
I'm not an aggressive rider by any stretch (short of WOT on US 395 for a few) so I run 42/42 measured cold and in any brand of tire. This ignores any advantages or disadvantages that might be found moving from tire to tire. But I'm ok with that. 42/42 helps me get the ST on the center stand. With a full tank it ain't easy bein' me. When the pressure drops to maybe 40 or below turning feels sluggish to me. I'm no racer.
Try 42/42 or 34/36 for
several hours in the saddle and then switch to the other. Try to note any changes in performance. Quicker/slower turn it? Quicker/slower transition from left to right to left to (you get the idea). Better or worse braking? Plowing or not in an aggressive turn? There are other very competent riders here who can give you better information on what to look for based on your riding style.
Unlike me once you find a satisfactory tire pressure scheme note that it may change if/when you change your brand or model of tire. And no- I have no recommendations on tires. Good luck with your quest.
[Or consider the post above mine instead]