Maybe I am behind with the times but I thought it is worth a mention that you can use farmfoods vouchers instore at tescos.
I have just got some coupons through my door and will try them out later!
£2.50 off when you spend £25
£5 off £50.
Hope they help someone.
p.s. my friend has verified that they do work!
Also apparently tescos check the dates on the vouchers!http://www.farmfoods.co.uk/