Everything at Northern Brewer is pretty high quality. That starter kit is as good as any. Their pricing is probably pretty close to retail, but with the 10% off it should be a good deal.
Don't get the second carboy option in the kit, either skip it or just buy a second 6 gallon carboy. You would save a few bucks and have two carboys that can be used as either primaries or secondaries. Unless you are doing lagers or high gravity Belgians you don't really need secondaries, so may as well have a more versatile setup.