Is there a difference between Clarins products in glass and plastic jars or are you paying for the packaging?

I want to buy Clarins Extra Firming Night Cream as a present. The RRP is £41 and it is available on Ebay etc. for £27 in the glass container that I want to give and for as little as £17 in alternative plastic container (both 50ml). Does anyone use it and could advise?

Thanks in advance.