The .tifs average between 5-10MB. I tried to attach one, but it was too large.
To create the raster dataset, I am using ArcCatalog 10.1.1, right clicking the database connection, selecting Import and then Raster Datasets. I leave the keyword blank and I do not make any changes to the environments. So far all of the rasters have imported successfully and are viewable from ArcCatalog 10.1 and ArcMap 10.1. It is only from the 10.0.5 clients that I get the Invalid raster message.
I have also tried importing the raster from ArcCatalog 10.0 into SDE 10.1. The rasters import correctly, but are not viewable in 10.0 or 10.1.