Capone's is brilliant mate! They have some VERY unusual concoctions there, as well as the usual standard-fare. There is one called Barnsley best and it has Chips, Kebab meat and chilli (or garlic) sauce all on the pizza! I forget the name of the one I have, but it has chopped beef burger, doner kebab meat and sheesh kebab. Gorgeous. They do a deal that is 2 10" for £8 delivered too.
Dominos is definitely the best. But like you say, ridiculously expensive, unless you take advantage of their offers. Every time we try anywhere else we're always disappointed.
If you know anyone on 02 you can usually get anything up to 50% of at dominos through priority moments
Can't remember using the Don Pepe in town, but the one at Cundy Cross is our current favorite pizza joint