For me Kettle Vegan Sheese crisps often get the half price for a quid in the supermarket's.
Some Tomato sauce crisps are vegan friendly too they are affa fine.

Aw man, I see myself as a bit of a crisp connoisseur!

Discos - a superb crisp.  Love the prawn cocktail and cheese & onion, but you cannot beat the original and best salt & vinegar.
McCoys - Love the salt & vinegar ones.
Cheese Doritos - YUM.
Big fan of Squares too, salt & vinegar of course.

I'd forgotten about tomato sauce crisps Buc, they are nice.  I also like Worcester Sauce ones.

My favourite crisp, however, are 'cheese tasters' from M&S.  Basically, a better version of wotsits.