I've just gone and bought 2 square pyrex dishes so that I can freeze lasagnes (smug emoticon). Has just occured to me that they may not be suitable for the Rayburn we're getting next month.
It says on the packet that they are conventional oven safe and I phoned the shop where I was told that they put it in their Alpha (?) and they are ok there.
Need a mumsnet opinion before I start cooking!