I have found that networking equipment, specifically wireless networking, fails in 9-15 months in my house. I have previously used linksys and netgear equipment. They were cheap, feature rich, and not long lasting.
I strongly wanted to enable wireless backups for my apple machines in my home. I also want to try to have equipment that might last longer. Trying another brand was in order. I have also seen a proliferation of wireless networks near my home - at times I have seen 15 or more other networks! I know professionals recommending Ruckus wireless networking equipment. I decided that for now Ruckus is out of my price range.
I have also found that there are portions of my home which are not covered by a single wireless router. I decided to finally attempt to work on that issue.
I bought an Apple Airport Extreme to be my primary firewall/NAT/Wireless access device, and an Apple Airport Express. Total outlay: about $300.
Many may decry the cost. I have also heard that getting an Airport Extreme with USB 2 provides much slower disk access for network-accessible disk than a Time Capsule. Having had a bad experience with a time capsule in the past and wanting more flexibility, I decided to stick to my plan.
Prior swapping my network equipment, I downloaded the Airport utility for my laptop via an ethernet cable (wireless was not working reliably). After swapping my prior wireless router for the airport express, things did not work. It was set as a repeater, not as my primary unit. In advanced settings, I set it up with the same internal address space and security setting as my prior router an voila - everything worked! I have numerous devices in my home - Wii, Tivo, a printer, and more. They were all able to connect. It was very easy. Having downloaded the software first was critical.
I downloaded the Airport Utility software for my iPhone as well at this point. It works quite nicely. Some spots in my house are still a bit problematic however - the coverage does seem better than before.
Next I added in the Airport Express. Bam - those holes in coverage are now gone! I have full access to my wireless network throughout my home.
I added a powered USB hub to my Airport Extreme and added a couple USB drives. One for backups of a couple laptops, and one for media data. I back up my iTunes as a separate job from time machine for my own reasons, and backups to this drive work find. I have a laptop backing up fine as well. I was unable to make the time machine backup encrypted via airport extreme. I was also unable to start the time machine backup via a local hookup to the laptop and then moving it over the network to continue backups. It forced a fresh entire backup. So I wiped the time machine backup disk and it is working fine (I did not need the old backups).
I am also trying out the Airport Express hooked up to a mini-stereo system. It works great. The greatest drawback is that if you set iTunes to use the Airport Express, then the next time you play music that is the default and you may not intend to blare music through those remote speakers...
So I'm very satisfied with my solution so far. There are drawbacks, some outlined above. The other main drawback: There is no easy way to get data about traffic going through my internet connection. I cannot easily see what internet accesses are happening as is a feature on all other wireless routers of this type. That is annoying. I have found instructions online to hack into the Airport Extreme to change this - I do not want to do this, I just want things to work.
Update: I have been using this gear for about 3 months. I have had no new problems; things work solidly other than having to reboot the extreme box a couple times (it was not responsive to remote management).