I have been buying the Genius three seed and brown breads. I am not a big bread eater anyway, so I keep them in the freezer and take out a slice when needed, defrost microwave for 20 seconds and then put in the toaster.
Sharing a toaster with wheat eaters is a potential for contamination. My second wheat ingesting mistake was putting some Genius in the toaster without protecting it. I then felt ropey for the rest of the day - so contamination is a real threat!
Many nutritionists and websites recommend using Toastabags (available from Lakeland!) which are designed for cheese toasties. However, I found the bags too big to fit in the toaster and they developed heat pockets which burnt both the toast and my fingers. I have therefore developed an ingenious alternative: take the Toastabag and cut off the top bit with the handles. The cut off the bottom and slit open one side, leaving you with a long, folded piece of material, which slots into the toaster easily. The bread then sits within this protective wrap, but because it is not entirely closed you do not get the nasty heat pockets. Each Toastabag packet contains two bags so you can cut them both up and then you have two, for when you want to toast a muffin or roll, or just want two bits of toast.
Here is the newly created "ToastaWrap" in use:
As with all gluten free eating, you are advised to wipe away loose wheat crumbs before using a shared toaster. If you are flush and have plenty of space, you could buy your own toaster, but I believe with care and your own ToastaWrap you will have no problems. It also helps to educate the rest of your family in being careful and wiping down worksurfaces after making wheat toast!