[popo]

How sealed do you really need it? I currently use a 7D as my all weather camera, including in the rain. It isn't waterproof, and with sufficient exposure to rain parts of it can start playing up like the joystick on the back, but dried out it is back to normal again. I'd have to be out in rain for several hours unprotected for that to happen though. Some people I know use rain covers, which may help further.



Similarly I use the 100-400L a lot. It isn't sealed either. Water eventually gets in through the pump action and condensation inside forces me to switch to a backup 70-300L which hasn't had any issues with water yet. Again the 100-400L would have to be out for some hours before it plays up.



Snow is no problem really, since it isn't really wet. Just dust it off before it melts and it does nothing.





My old 50D in snow. I didn't realise it was that deep before I put it down...





Same 50D when I slipped in snow and I landed on top of it. Dusted it off and it was fine.





7D+70-300L after I took shelter from a heavy rain shower. The camera is more resistant than I am! Note it looks a bit mishapen as I used my compact, which doesn't appear to do distortion correction well at close range...





Condensation in the 100-400L after using it in rain for some hours. I leave it alone with the caps off, and it clears soon enough.