5.5 and 3.5 no problems at all.
i think it's really important to remember that males have evolved with foreskins. it is a normal and essential part of the male genital anatomy. it is there for many reasons. most men worldwide have their foreskins and no problems whatsoever. yes, occasionally, infections do occur, just as they occasionally occur in girls/women. how many of you mamas have had a urinary tract infection and how was it treated? the real problem is the US doctors that really have no clue as to how the foreskin functions and how valuable it is and how to treat any minor issues. the male prepuce has literally been written out of medical textbooks in the last 75 years! the only thing they know about foreskins is how to cut it off.
so there was this one time where ds was playing outside naked and got poked in the penis by a nasty weed. his foreskin swelled/ballooned up, it looked awful! called the doc, he asked if ds could pee normally, he could, so all was fine. doc said the foreskin protected the glans in this case, if ds did not have his foreskin, the glans would have swollen up and that could have been bad. yay evolution!