as you're in the US, I presume you are using the purple breeze block/super famicom, (pal / euro ver is 17.6% slower and nasty large borders on top of4:3 on 16;9 tv)
the pins are different on the multi av socket output ( compared to the ntsc snes), pal snes scart cables will not work on ntsc machine ( classic nintendo fiddle with the output region lockout) see linkhttp://nfggames.com/forum2/index.php?topic=3413.0
you need super famicom rgb compatible scart for pal tv cable.
please note it's widely known some certain korean tv may not handle rgb, but it's probably unknown territory using rgb to component video converter, so quality issue may happen or not is another matter, whether it's lag, colours, flickering, etc
nevertheless, the best ( but expensive) option for snes visuals is using a xrgb2/2plus/3/mini, original japanese rgb for japanese rgb 21 pin, shvc-010 and either super nintendo (purple breeze block, i am using) and super famicom which i have. pc engine and ps one/ps2 is used via xrgb 2 plus as well as second ps2 with a hd box pro