Here's what KMC claim about their different chains -
X10-73 is grey/grey, X10-93 silver (nickel plated) outer plates, grey inner plates. X10 EL is full nickel plated (inner & outer plates) and light weight. Also X10 EL is more durable than X10-73 and X10-93. If you are an active rider (Road or MTB) I recommend you X10 EL: good anti corrosion protection, lighter weight and better durability. If you are a daily commuter even in winter times you could also choose for X10 EPT which is a real Anti Rust chain.
So if that
Decathlon chain is an X10 SL or EL then it looks like a real bargain.
@Hacienda71 - are you sure the Decathlon chain is one of the above rather than one of the cheaper X10-73 or 93 types?