waterproof case for camera for costa rica trip

I'm going to Costa Rica for spring break.
I know that I need to protect all of my stuff from the rain and/or humidity.
I have a Canon PowerShot A550 digital camera.
They sell waterproof cases called Aquapac on Amazon.com (and other places).
These are supposed to keep your camera dry and still allow you to take decent photos.
Has anyone used Aquapac, or does anyone have any other suggestions?
I don't want my camera to get ruined, and I still want to have clear pictures.
Thanks.

Hey, I'm going to Costa Rica on Spring Break! With the Brown School - you, too?
Can't help with the waterproof case - they all look so clumsy I never got one. There's a digital camera (Pentax I think) that's truly waterproof/submergeable (Robin - spelling ruling, please).

Hey, you must be Hannah's dad.
I'm Evan's mom.
Yes, we are going on the Brown School Costa Rica trip.
I went ahead and ordered the Aquapac. It just came today, so I'll have to try it out.
I'd hate to get over there and have my camera ruined in the rainforest!

Leave the Canon at home and go to Sam's and get an Olympus Stylus 1030SW for $270. You can take it underwater with you.

I give it my photojournalistic seal of approval.

Hi Evan's Mom, yes, I am Hannah's Dad. See you in Costa Rica if not before. I gave Evan a ride once and thought it was kind of unusual that she was so into the Grape Leaf (we drove by it) - now that I know her Mom's a foodie, it makes sense.
I've been wondering about the camera options for the trip as well. I have a Canon SLR and would enjoy using it there, but not carrying it around and worrying about it. Maybe I'll get the waterproof Olympus, what with the photojournalist seal of approval and all. The cost is a bit higher than I like, though. Anyone have ideas on buying used camera gear? Besides a point-and-shoot for travel, I would like to get more glass for the SLR. I really want a
Canon 17-55 zoom f2.8, but cannot pay $850 (lowest I've seen for this lens).