There is no comparison when it comes Glastar's grinding heads. They outperform and outlast most other heads. The secret is their unique diamond bonding that eliminates peeling, creating a uniform surface that lasts.
Standard 100 Grit is the standard replacement for the Glastar G8 grinder as well as the Inland Impulse and Wizard. One inch diameter bits do not "bite" into the glass quite as much as 3/4" diameter bits, creating straighter edges and gentler curves.