180/55 is all you need on the street & it is cheaper
for the track a 180/55 works good
but once you start getting quick you start running off the edges of the tire quite easily
that is when a step up to the 190/55 is worth it
If you feel that you NEED the 190/55 on the street, then you are either pushing your luck risking life & limb on the street or you really have to work on your riding technique.
