You're an "electronics designer" but you're talking about "form factor" which has nothing to do with sourcing FPGAs for RAM manufacturing..
High density has identical "form factor" to low-density, often times even with chip and filter footprints.
You're not even comprehending the subject and instead going against-the-grain based on a fragment of the thread title. Be relevant and consistent or don't bother..
Note: This post was edited by a forum moderator to edit out personal attack on 03/16/2012 at 2:24 PM PT