Well, there be a lot of people knocking it without trying it.
I've tried it.
I have $.99/each Czech Republic hockey pucks from Dunham's.
I bought them like 3 months ago so I could set my cab on the frame without having to cut a hole in the floor (2wd cab/low hump) for the monstrous 465 so I could drive it on the trailer.
I have brand new GM OEM body mounts everywhere. So they're really soft.
Combine the OEM body rubbers with two hockey pucks stacked on top and things get really squishy. Like everything squishes so much the bolts are loose when flexing. I only have one under my core support. It doesn't flex as much.
Mine seem to be holding up really well. However, I know some people that have had problems with them splitting. I suspect it is engine heat related.
If you only need 1" and don't mind checking them on your pre-run maintenance checklist then I say go for it. If the other people scared you, just have the machineshop cut you 3" cold rolled or have them make you plates out of 1" aluminum.
I have Tim84K10's old 3" body lift that I'm eventually going to cut down to use once I figure out exactly where my transmission and transfer case are going to rest. Oh, and decide whether or not I'm going to make a custom transmission tunnel.