Just thought I would let you guys know if your are looking for a good rugged case for the HD7 the Poetic Revolution is the way to go. Can't post links but it can be found on amazon for $30 and prime shipping.
I received mine last week and it is really well built and you can't beat it for $30. The quality is on par with Otterbox Trident, and Gumdrop. I contacted the seller about making a case for the 8.9 and they said if this one sells well enough they plan on making one for the HD 8.9. They already have them for the Nexus 7 and 10.