I've come to realize that my grocery bag panniers (with a rain cover) are not going to cut it if I continue to ride in the rain. Can anyone recommend waterproof panniers that work well for commuting--not too big, easy on/off the bike, and preferably brightly colored? I've done some web shopping, but it's hard to decide when you can't actually touch them, and it's hard to get a sense of the size. Here are a few I'm looking at:

http://www.wallbike.com/ortlieb/rollerplus.html
http://www.rei.com/product/47848812.htm
http://www.rei.com/product/37165.htm
http://www.rei.com/product/48131033.htm
http://aebike.com/page.cfm?PageID=30...ils&sku=BG2615
http://www.arkel-od.com/panniers/sam...asp?fl=1&site=

Thanks for your help!