I have a 1084S with the following systems all connected through a scart switcher. I am not keen on using LCD displays with old systems.
A1200 - RGB
C64 - Composite
Spectrum+ 128 toastrack - RGB
BBC Micro model B- RGB
NES - Composite
N64 - Composite
Mega drive - Composite
Atari 2600 - Composite modded
I have got a CD32 with RGB mod connected to my 55" LCD in the living room which doesn't look to bad.
1084S version - http://gona.mactar.hu/Commodore/moni...-P_ebay.de.jpg
Scart Switcher - http://ecx.images-amazon.com/images/...500_AA300_.jpg