Engine coolant temp sensor

Hi this is my 1st post.

I have a Fabia on a 53plate 1.2 HPI

The EMS light came on, so I asked an aa bloke I know to plug his thingy in and have a look. It came up

"Engine Coolant Temperature sensor circuit 1 high"

He then reset the EMS, the light has now gone out, and has stayed out.

1. Would you say the sensor just need replacing or should I wait for something else to happen? I have no other symptoms.

2. If yes, they are £30 from VW or Skoda or £15 on websites, which should I go for?

thanks in advance