Quality differences exist in SCART cables. While a proper SCART cable uses miniature coax cables for the video signals, cheap SCART cables often use plain wires for all signals, resulting in a loss of image quality and greatly reducing the maximum cable length. A common problem is that a TV outputs a composite video signal from its internal tuner, and this is induced or cross-talked onto an incoming video signal due to inadequate or non-existent screening on a cheap SCART cable; the result is ghostly images or shimmering superimposed on the incoming signal. To non-destructively verify if a SCART cable uses coax cables, one can unscrew the strain relief at the SCART connector and fold open the plastic shell.
Although using higher-quality cables might help in reducing a 'ghosting' effect, a more permanent method is to remove pin 19 from the SCART plug that is put into the TV. Pin 19 is Video Out, and removing it prevents a signal from being broadcast by the TV into the cable in the first place, so it cannot cross-talk with the incoming signal. Cheaper SCART plugs can sometimes have the pins pushed inside the connector housing so as to remove it in a non-destructive manner (and thus allowing for its replacement in the future should the need arise by simply unscrewing the housing and pushing the pin back through its hole), though sometimes the pins are fixed in place on the inside by glue or rubber and can only be removed by forcefully twisting them off entirely. Generally though, for a standalone TV there is no need for video output on the TV end of the SCART plug, so in the majority of cases removing it completely should not be a problem. Whichever way it is done, however, once it is the SCART is rendered incapable of transmitting a video signal from that end of the cable, so it would be wise to mark it as such for future reference.
Gold-plated SCART connectors, which do not corrode and deliver a cleaner signal, might be preferable, although they always cost more than nickel ones. However, gold-plated connectors only give better performance when both plug and socket are gold plated. Gold and nickel are galvanically very different metals, and although inserting a gold-plated plug into a nickel plated socket may make a small difference at first, any atmospheric moisture that is present near the connector will cause an electrolytic reaction between the dissimilar metals. This will result in the nickel-plated connector corroding much more rapidly than it would if both connectors were nickel-plated. For good long-term connection quality it is always better to use matching connector materials.