You're kidding, right?
The 8500/9500 cases require a "bit" of extra work to get the motherboard out. All the PCI cards have to be taken out, all the connectors to the motherboard have to be disconnected, a screw taken out, the power button assembly needs to be carefully removed, then the logic board is slid to the front of the case. That seems like a lot of work to add RAM. Granted, after you've done this a few times, the disassembly process gets easier and faster.
However, all you need to do is look at the design of the 8600/9600 to see the improvement. Adding RAM? Drop the side door down. Finished.
The 8500/9500 cases require a "bit" of extra work to get the motherboard out. All the PCI cards have to be taken out, all the connectors to the motherboard have to be disconnected, a screw taken out, the power button assembly needs to be carefully removed, then the logic board is slid to the front of the case. That seems like a lot of work to add RAM. Granted, after you've done this a few times, the disassembly process gets easier and faster.
However, all you need to do is look at the design of the 8600/9600 to see the improvement. Adding RAM? Drop the side door down. Finished.