Oil based Radiator ( room heater)

Hi Dimers,
Recently I visited a local electronic store for purchasing Oil filled room heaters, it is very popular retailer in electronic.
They have lot of oil filled room heater of 2013-2014 making and they are ready to give them in 40% discount, for example: oster 9fin is costing approx Rs3500 and the product will have 1 year warrantly as well.
I am in doubt whether I should purchase the old piece or not however they confirm that the piece will be sealed pack and new piece.
Can someone kindly help whether I should purchase the old stock of oil filled room heater. Is there any issue with this or it is fine to purchase the same.

Regards,