On average, a link belt it is an improvement over a cheap stock v-belt. They reduce the vibration issues of a thumping v-belt that has a set or a zig in it. However, link belts are not always an improvement over stock belts in every way....the link belts are less aerodynamic and make more wind noise than a serpentine or v-belt (but the lack of high speed thumping makes them sound quieter than a bad belt), plus not all v-belts have vibration issues so the difference with a link belt can be barely noticeable if that's the case. A ribbed serpentine belt has more efficient power transfer than either a link belt or a single v-belt...there's more belt surface area contacting the pulley, so there's less slippage. It's worth noting that there are some really good grades of cogged v-belts that don't usually come stock on wwing machines.