Plugs with gold plated pins are indeed more reliable, but if the socket on the equipment is a cheapo one with plain copper (or worse) connectors, then the posh plug is not going to yield many benefits.
When we bought our new television three years ago, the shop tried to sell me £40 SCART leads. I thanked them, and went to the local chap and bought leads for under a fiver. They've been fine - never a hiccup. If they did misbehave, they'd get a blast of Servisol and a wiggle before being pushed back in.