I've been using wireless USB adapters for a few years and have found them to wok well for the most part. I've had the most success using Linksys USB adapters, other USB adapters such as DLink ones (thumbsized) that I have used had smaller range, but would work fine if I was in the same room as the router or within 20ft of the router.
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3DMark11: P7402 |3DMark Vantage: P27054 |3DMark06: 25499