I have also used the Platinum product line. I like them all very much! Love the wash! Smells awesome, and I am comparing them to Wizards Products!
I would compare the Sealant to
Klasse (I have had bad experience with Klasses once or twice, but it could have been an opperater error!-love the stuff either way!), Shine Master, and/or Race Glaze. No experience with
Blackfire or Zaino (yet).
Overall, thumbs up on the Platinum!