I did some research last time I changed my oil. Slick 50 seems to be a bad idea because of the ptfe. I found extralube zx1 and it had good reviews and no ptfe.
Engine ran quieter and smoother with more power.
Was quite a lot of info out there. Will try and find the links tomorrow, but the main consensus seemed to be oil on its own simply meets manufacturers specs, whereas these can be improved upon with additives, but do not use any with ptfe due to blockages and such in oil channels.