Re: One modern trend to mention with Acer/Asus
"Is that they are moving to solid undertrays."
Is that new? I've a Acer Netbook bought in 2010. Upgrading the RAM by 1GB meant 'almost' disassembling the entire thing to base components in much the manner you describe. It took me twenty minutes (plus several hours pouring over the disassemby manual for repair staff and a few youtube videos - I really didn't want to make a mistake).
At least there was no glue used anywhere...