You get what you pay for. The cord/rope is of different construction, smaller in diameter and subject to failure sooner.
They are available with different size pull ropes. My saw takes a 3.5mm rope. Starter Grip for STIHL Models - ElastoStart Ø 3.5 mm | eBay
One for a stout saw. Starter Grip for STIHL 038 up to 088 & MS 380 up to MS 880 Models [ElastoStart] | eBay