Which Wiresless router is best?

Hello, I am currently having issues with a Wireless Router/ 4-port switch combo I have. It is a Linksys Wireless G Router WRT54G v5. I bought it in 2005, so its rather old but I hear good things about older models compared to new ones because the newer simpler circuitry can complicated the flow of data, but not sure if that's myth or fact. Regardless, when I bought the Router I was told it could easily handle 4 wired devices and 4 wireless simultaneously, however that was in 2005, I'm not sure the router can keep up anymore. I have the current firmware and the appropriate gaming ports open. The problem I'm experiencing is an intermittent or inconsistent connection. I have two Xbox 360's wired to the Router and I run a desktop computer wireless. Occasionally guests will add another wireless device or two when they browse while visiting. On the 360's we constantly experience disconnects and they occur most often during downloads (such as demos or add-sons) and when streaming netflix. Weird enough though the connection seems find for the most part during online gaming on the 360's. It does "glitch out" a lot where it appears other players are "teleporting" around the screen as opposed to running, but rarely do I experience a full disconnect. I have no problem investing in a new router if that's the case, I just need some help on deciding on a model. I'd like to stick with linksys if that is my best bet. We will be adding a 3rd 360 after the holidays when my room-mate gets one so I'll need a router that can handle 3 xbox 360's through wire, plus a desktop wireless. At times but rarely all 4 devices will be used. So whether it be altering the performance of my current router or investing in a new one any and all advice is appreciated. Thanks