Pizza delivery bags are not something I can claim any particular expertise in, but from what I have read at the PMQ Think Tank and elsewhere, the thermal insulated bags from Pizza Bags (http://www.pizzabags.co.uk/
), which apparently imports the bags from a U.S. company called Bag Solutions (www.deliverybags.com
), are considered to be a good product.
The bags used by Domino’s are apparently sourced by CookTek (see http://www.cooktek.com/productsVaporVent.html
). If you look at the Rep Finder tab, and click on Europe you will find the name of the distributor in the UK (by clicking on England on the map). The CookTek units are apparently expensive but considered worth the money (see, for example, http://www.pmq.com/cgi-bin/tt/index2.cgi/read/18779
). However, the CookTek bags are electric bags that have to be heated. The bags are most useful where the delivery distances are great and where the driver is likely to be on the road for a long time.
I realize that you are in the UK, but for reference purposes, you might also want to take a look here: http://www.pmq.com/mag/2002winter/hotbaglist.shtml
. You will find both Bag Solutions and CookTek in the list of bag suppliers. Since links are provided to other companies who may sell in the UK, you might be able to do some research on those.
You might also want to do a search at the PMQ Think Tank to get more hands-on information. You might use “pizza bags” (both words, without quotes) for search purposes. Since PMQ recently changed its forum software, you will want to search the archives also (they are separate from the posts since the software was changed).