Last summer in the net a new bowler bowled to me, his first delivery jumped from so close to me that I couldn't react to it, and the ball hit me full on the grill! At that time I was wearing Albion classic steel grill helmet. Felt blow on the grill, that's it. Played next delivery as of nothing was happened! Wouldn't say that delivery was quick but it was definitely crisp
Checked later the grill, couldn't see even a scratch.
Since then I've bought Masuri Test Titanium Helmet, which is definitely lighter than Albion one.
You don't want to get hit on the grill, but if you do, then want to be safe and sound.
I think steel grill helmets are as good as titanium ones when come with higher range helmets.