The biggest dimensional difference that you will have is thickness. ERC has very low bend resistance so it has to be a lot thicker to make draw weight. I still mess em up by getting them too thin when I'm roughing them out. I haven't hard backed one, so I don't know how that effects the final dimensions. One of the fellas that makes laminates will have to answer that. I hope to see you at the classic. As it stands right now, its pretty iffy on whether or not I will make it as well. Josh