Does anyone know what receiver they'll "swap" in to replace MPEG-2 "standard" receivers? I've got a pair of old Sony B-10's and a Samsung. Will whatever the replacement units are be able to receive the HD data stream or do I need to bite the bullet and buy HD receivers as replacemements. I saw one post where they replaced an HR10 with an HR21. Any idea if the replacement units will be H21s?