As a user of Hybrid Ceramic bearings (Ceramic Balls with Steel races) living in Florida, I have some experience with wet bearings. How much water will affect hybrid ceramic bearings depends on the type & quality of steel used in the bearings... My TwinCam ILQ-9 Black Ceramic Ball bearings were used durring the Eddy Matzger Clinic earlier this year in which they got quite wet due to rain. I removed them & put the ILQ-9 Classics in for the remainder of the weekend, intending to thoroughly clean & dry the Ceramics, but I forgot about them till a month later...

however a quick inspection revealed
no rust 
, so I put them back in & they rolled like new. Some steels used in some current bearings can start to rust in just a couple of hours, especially some of the generic bearings (including hybrid ceramics) on the market.
In the case of full ceramic bearings, water doesn't matter, in fact they are impervious to most chemicals (the bearing retainers are the weakest link, usually made of Nylon, or in better quality full ceramics, Teflon) & can even be used underwater... not that you'd want to skate underwater

or pay up to $700 for a set of bearings
I buy about 90% of my wheels from one of 3 sources: Vendor booths at races,
http://www.inlinewarehouse.com, &
http://www.adamsinline.com. The rest are purchased from whoever has the best deal on the specific wheels I'm looking for be that someplace local, or an online vendor.
For training bearings, I use VXB bearings which I buy direct in bulk
http://www.vxb.com/ Their ABEC-7 bearings are just about on par with BSB ABEC-7 bearings, but a lot cheaper (I paid ~$50 for 100 bearings including shipping)
http://www.vxb.com/page/bearings/PROD/kit708 Same bearings, but I got mine from one of their Ebay auctions a couple years ago.
For race bearings, I use the TwinCam's which I ordered direct
http://www.ilq9.com/