I don't know anything about front panniers in particular, but you really can't go wrong with Ortliebs. Excellent waterproofing: I have the Bike-Packer Classic rear panniers and have no concerns at all about throwing my fancy laptop and important papers in mine and commuting in pouring rain. Super-durable (and even if you somehow manage to damage them, Ortlieb will gladly fix it, from what I hear). And I wouldn't worry about weight at all with those: in my experience, the bags hold plenty more weight than I can really lift/carry in my arms, and more than my bike itself can carry without causing weird handling issues. And they'll adjust to fit pretty much any rack (although I admit I don't know much about front racks).
You might want to look at them up close before choosing roll-top vs. another closure system, depending on exactly what you're going to be carrying around. The roll-tops are popular and perhaps more waterproof in the most extreme cases (i.e., immersion), but I found the Bike-Packer/Sport-Packer design to be better for me. The drawstrings under the buckle flap (image: http://www.hammerkauf.de/images/product_images/popup_images/17515_3.jpg) allow for flexibility, i.e., some serious overstuffing, which makes it easy to carry weirdly-shaped things or absurd volumes of stuff. Doesn't matter so much on a day-to-day basis, but helps with things like shopping for groceries. If that kind of thing may come up for you, it's worth looking at the other design.
ETA: link to the Sport-Packer front panniers since it looks like REI doesn't have those: http://www.ortliebusa.com/CartGenie/prod-27.htm