How to connect 2 amiga on one 1084s monitor RGP

[S0nic]

i have a500 and a600 how to connect this 2 computers on one 1084s monitor with rgp cables, i find this switcher


http://www.krp.com/D-SUB-SWITCH-BOXES_p_1352.html


so what i need i think is:
-one rgp cable male to male 9 pin - with this i will connect switcher and monitor
-two rgp cable  male to female 9 pin male and 23 pin female

if i write something wrong correct me

ps
is rgp better picture quality port then scart solution for amiga

[S0nic]

and it's expencive way , it's better for me to buy second monitor because buying monitor is cheaper than this plan with switch


i get this cable with 1084s for what computer is this cable c64 , amiga?