I can grind on non 4.5 decks, I ride a 5" though. All im saying is that they arent as good as TSI's and other fully boxed 4.5 decks for grinds and they're weak af, plus its pretty much impossible to get decent 50-50s on them.I've ridden one.
They're sick.
if you need 4.5 inches to do grinds, then you need to practice more.