I've run Shinko's front and back, haven't wavered from the rear yet, alternated the front tire between brands, never an issue that I felt.
Reference tire pressure, the front tire is at least 39 -40 lbs for this heavy bike. Anything less, regardless of brand, will have my front start cupping. When the front does get lower air (sitting up for an extended time and dummy me doesn't check tire pressure pre-ride) I can feel it.
Steering head bearings need attending to also, might be worth a check.
HTH