Double pizza is only worth having if you're going to order delivery. Somehow the pizza they have at the shop isn't all that fresh and I can't really say it's particularly memorable.
The neat thing about Double pizza is that they have halal pepperoni. For someone who doesn't eat pork, it's nice to be able to order an all dressed pizza.
Their cheese and sauce is ok, I think the issue I have is with the bread, there's something about it that gives the overall product a slightly cheap feel.
That said, it is cheap, to there's that. Personally I'd pay a few bucks more and get Dominos, unless I'm in the mood for pepperoni, then I'll order Double Pizza.