Interesting comments Chris. I have 2 friends in the US who both, approx 10 years ago, had DCIS and opted for double mastectomy. One had big boobs and ended up with smaller ones, the other had very small boobs and ended up with bigger ones -- both were delighted with the new boobs. I'm not sure to what extent getting new boobs was a factor in their decision making. Both have referred to their strategies as being over the top vis the cancer they actually had, but neither have had a recurrence so far.
In my case (very small tumor (5mm), type 1, clear lymph nodes, no family history) I think the radiotherapy does make sense (even though I am dreading it).
In your case Jenn, what is the story with your cancer? Was it big, how aggressive, how were your nodes?
Whatever the case, if you are thinking that a mastectomy may be a better option, I would do 2 things: go see your surgeon and put that to him/her; go see your GP and tell them what you are thinking and that you want a referral for a second opinion. By talking it through with the GP and a 2nd surgeon, you (hopefully) will find that your views on it all will clarify.
Good luck and please post what you decide.
Esther