I used to heat my bags in the microwave, until one night the electricity failed just before my 10 pm exchange. I bravely went ahead and did the exchange and didn't have any problems (the nurse had said I might cramp). Being the lazy person I am, I never attempted to heat my bags again. Just a thought.
I think another major difference over here is that we are allowed to swim in the sea! Are you guys? Apparently our renal people believe the salt water kills the bacteria. I love swimming and I really miss it, so I love getting the chance to have a bit of a swim.