I have a cheapo bike ( worth maybe £70 used) its pretty scratched up with a ripped seat but still it's bright red so it still stands out and still looks decent when washed 
I don't really have a lock and I rarely leave it anywhere anyway,but I want to start commuting with it and it would suck if one day I come back and I don't have a way to get back home.
This is the lock I want to buy ( actually It's free because I have a credit on that site and I only want to get it because it costs me nothing and I need to spend the credit
)
https://www.ffx.co.uk/tools/product/Masterlock-Mlk8228E-3520190941930-1M-X-18Mm-Cable-Blue
I understand its not the cheapest poundshop lock, but still its a cable lock with just some added protection to the cable itself so probably not very good.
Is it worth to get it or am I wasting my time?

I don't really have a lock and I rarely leave it anywhere anyway,but I want to start commuting with it and it would suck if one day I come back and I don't have a way to get back home.
This is the lock I want to buy ( actually It's free because I have a credit on that site and I only want to get it because it costs me nothing and I need to spend the credit

https://www.ffx.co.uk/tools/product/Masterlock-Mlk8228E-3520190941930-1M-X-18Mm-Cable-Blue
I understand its not the cheapest poundshop lock, but still its a cable lock with just some added protection to the cable itself so probably not very good.
Is it worth to get it or am I wasting my time?